Let a(n) denote the n-th term in the sequence. Because the terms are in arithmetic progression, there is a fixed number d that separates consecutive terms, so that starting with a(1) = a, the next few terms are
a(2) = a(1) + d = a + d
a(3) = a(2) + d = a + 2d
a(4) = a(3) + d = a + 3d
and so on, up to
a(n) = a + (n - 1) d
We're given that the 30th term is 98, so
a(30) = a + 29d = 98
The sum of the first 30 terms is 1635, so that
[tex]\displaystyle \sum_{n=1}^{30}a(n) = \sum_{n=1}^{30}(a+(n-1)d) \\\\ 1635 = a\sum_{n=1}^{30}1 + d\sum_{n=1}^{30}(n-1) \\\\ 1635 = 30a + d\sum_{n=0}^{29}n \\\\ 1635 = 30a + d\sum_{n=1}^{29}n \\\\ 1635 = 30a + \frac{d\times29\times30}2[/tex]
so that
30a + 435d = 1635
Solve the equations in boldface for a and d. I'll eliminate a and solve for d first.
-30 (a + 29d) + (30a + 435d) = -30 (98) + 1635
-30a - 870d + 30a + 435d = -2940 + 1635
-435d = -1305
d = 3
Then
a + 29 (3) = 98
a + 87 = 98
a = 11
Choose ALL of the ordered pairs that are solutions to the equation.
5y = 2x - 7
a) (6, 0)
b) ( 7, 21)
c) (8, 18)
d) ( -3, 4)
b) ( 7, 21)
Step-by-step explanation:
5(7)=2(21)-7
35=42-7
35=35
Answer:
None of them
Step-by-step explanation:
a: 5*0=2*6-7 False
b: 5*21=2*7-7 False
c: 5*18=2*8-7 False
d: 5*4=2*-3-7 False
Please HELP! ):
The measure of an interior angle of a regular polygon is eight times the measure of one of its exterior angles. How many sides does the polygon have?
find value of the variable
Answer:
x=10
Step-by-step explanation:
16/24=(x-2)/12
or, 16/2=x-2
or, 8=x-2
or, x-2=8
or, x=10
Answered by GAUTHMATH
What is the measure of ∠
A. 6°
B. 42°
C. 60°
D. 49°
Answer:
<XYZ is equal to 49°
Step-by-step explanation:
Set the two expressions equal to each other so 7x+7=5x+19. Subtract 5x from 7x and 7 from 19 which is equal to 2x=12 that means x is 6. then plug 6 into (7x+7) which is equal to 49.
what is 8/9 divide 2/3?
Answer:
4/3
Step-by-step explanation:
8/9 ÷ 2/3
Simplify the complex fraction.
4/3
Step-by-step explanation:
8/9 ÷ 2/3
Simplify
4/3 is the correct answer
which one is the correct answer
Answer:
B.
Step-by-step explanation:
2x - 31 = - 2x - 314x = 0x = 0Other equations don't have any value of x.
Answer:
[tex]2x-31=-2x-31[/tex]Because if you see.. The component of x will get canceled in each of the other 3 options.. ( 2x - 2x) which means no solution.. In option B.. 2x + 2x will give 4x..= 31-31 = 0..
-------------------------
Hope it helps...
Have a great day!!
help help............
Answer:
please send the pic again clearly
Answer:
I hope it will help you
Step-by-step explanation:
please make me brainlestthank u
Please need help explanation need it
Answer:
308 m^3
Step-by-step explanation:
The volume is given by
V = l*w*h where l is the length , w is the width and h is the height
V = 7*4*11
V = 308 m^3
in a shipment of 10,000 headlights, 5% are defective. what is the ratio of defective headlights to non-defective headlights
Answer:
19:1
Step-by-step explanation:
There are 10000 headlights. If 5% are defective, then 500 are defective. Since we took that 500 out, we get 9500 good headlights. The ratio is 9500:500 or 19:1
The ratio of defective headlights to non-defective headlights will be 19:1.
What is the percentage?The Percentage is defined as representing any number with respect to 100. It is denoted by the sign %. The percentage stands for "out of 100." Imagine any measurement or object being divided into 100 equal bits.
In mathematics, ratios are used to determine the relationship between two numbers it indicates how many times is one number to another number.
There are 10000 headlights. If 5% are defective, then 500 are defective. Since we took that 500 out, we get 9500 good headlights.
The ratio will be calculated as below:-
Ratio = 9500:500
Ratio = 19:1
Therefore, the ratio of defective headlights to non-defective headlights will be 19:1.
To know more about percentages follow
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Mọi người giúp em với
Answer:
bka bla bla bla sorry I newbie
Can someone help me with this math homework please!
Answer:
(-3,-6) and (-3,2)
Step-by-step explanation:
A line with an undefined slope is vertical. In this case it must have x coordinates equal to -3
If x=3 ,y=4 than what is the value?
If m angle PQR = 141", find each measure.
Answer:
x=6
pqs=82
sqr=59
Step-by-step explanation:
13x + 4 + 10x - 1 = 141
23x + 3= 141
23x = 136
x = 136/23 = 6
~~~~~~~~~~~~~~~
pqs = 13x + 4 = 13(6) + 4 = 78+4 = 82
sqr = 10x - 1 = 10(6)-1 = 60 - 1 = 59
Answer:
x = 6
Angle PQS is 82
Angle SQR is 59
Step-by-step explanation:
13x + 4 + 10x - 1 = 141
Group like terms : 23x + 3 = 141
Subtract 3 from both sides to get 23x = 138
Divide both sides by 23 to get x = 6
Angle PQS: Plug 6 into x for 13x + 4 = 13 (6) + 4 = 82
Angle SQR: Plug 6 into x for 10x - 1 = 10 (6) -1 = 59
please help!!!!!!!!!!!
What conclusion can be derived by comparing the central tendencies of the two data sets?
A: (7, 6, 3, 1, 6, 2, 4, 6, 3, 5;
B: {2, 2, 2, 3, 4, 5, 2, 8, 7, 6}
Doanh nghiệp bán trả góp 1 bất động sản có giá thanh toán là 32.000trđ . Thu điều cả vốn lẫn lãi trong 10 năm với lãi suất trả chậm là 10% / năm . Xác định số vốn phải thu ở năm thứ 6 ?
Answer:
Step-by-step explanation:
the sum of three consecutive numbers is five times the difference of the middle number and 22. find the numbers.
Answer:
The numbers you're looking for are 54, 55, and 56.
Step-by-step explanation:
x + (x + 1) + (x + 2) = 5 * (x + 1 - 22)
3x + 3 = 5x - 105
3 = 2x - 105
108 = 2x
x = 54
x + 1 = 55
x + 2 = 56
Scarlett made a profit of $250.00 with her mobile car wash company
Not enough information to solve..... Please make your question more clear
What is the recursive formula for this geometric sequence?
-4, -24, -144, -864, ...
= -4
O A.
an =
2n-1 • 30
OB.
la = -4
ar = 2n-16
fa
= -6
C.
= 2n-1 • 30
= -6
O D.
lan
ar = 2n-1.4
Answer:
a1 = -4
an = an-1 * 6
Step-by-step explanation:
-4, -24, -144, -864, ...
First find the common ratio
Take the second term and divide by the first term
-24/-4 = 6
The common ratio is 6
The recursive formula is
a1 = -4
an = an-1 * 6
PLEASE HELP !!!!!!!!!!!!!
Answer:
the 3rd won for sure
Step-by-step explanation:
hope I helped
Answer:
C
Step-by-step explanation:
The coordinates are all in (x, y) form.
X is how left or right
y is how tall.
If you just look for the individual coordinates given, you will see that all of the Coordinates in C are on the graph.
I hope this helps!
Can I know the answer for the above questions
Answer:
Step-by-step explanation:
Ashish deposite rs 1000 every month is a recurring deposit account for period of 12 months. If the bank pays interest at a certain rate p.A. And ashish gets 12715 as the maturity value of this account at what rate of interest did he pay every month
Solution :
Given :
Principal amount, P = Rs. 1000
Time period = 12 months
The maturity value = Rs. 12,715
We know that,
[tex]$ SI = \frac{PTR}{100}$[/tex]
[tex]$SI = 1000 \times \frac{n(n+1)}{2 \times 12} \times \frac{R}{100}$[/tex]
[tex]$SI = 1000 \times \frac{12(12+1)}{2 \times 12} \times \frac{R}{100}$[/tex]
SI = 65 R
So we know,
maturity value = principal amount + SI
12715 = 1000 + 65 R
65 R = 12715 - 1000
65 R = 11715
R = 18%
So the rate is 18%
Answer:
[tex]R=11\%[/tex] p.a.
Step-by-step explanation:
Given:
the principal amount deposited each month, [tex]P=Rs. 1000[/tex]
amount after maturity of one year, [tex]A=Rs. 12715[/tex]
We have the formula as:
[tex]I=\frac{PR}{100}\times\frac{T(T+1)}{2\times 12}[/tex]
where:
R = rate of interest per annum
T = time in months
[tex]A-12P=\frac{PR}{100}\times\frac{T(T+1)}{2\times 12}[/tex] [since the principal is deposited each month]
[tex]715=\frac{1000\times R}{100}\times \frac{12\times 13}{24}[/tex]
[tex]R=11\%[/tex] p.a.
Question 2 of 10
Which of the following can you determine, when you use deduction and start
from a given set of rules and conditions?
A. None of these
B. What may be true
C. What may be false
D. What must be true
SUBMIT
If a 750 ml bottle of juice costs £1.90 and a 1 litre bottle of the same juice costs £2.50 then the 750 ml bottle is better value.
Answer:
The 1 liter bottle is better value
Step-by-step explanation:
Cost of 750 ml = £1.90
Cost of 1 liter = £2.50
1000 ml = 1 liter
Cost per 250 ml
750 ml / 3 = £1.90 / 3
250 ml = £0.6333333333333
Approximately,
£ 0.633
Cost per 250 ml
1 liter / 4 = £2.50 / 4
250 ml = £0.625
The 750 ml bottle is not a better value
The 1 liter bottle is better value
Show Workings.
Question is in attached image.
Answer:
A.]A chord of a circle of diameter 40 cm subtends an angle of 70° at the centre of the circle.
Solution given;
diameter [d]=40cm
centre angle [C]=70°
(a) Find the perpendicular distance be tween the chord and the centre of the circle.
Answer:
we have
the perpendicular distance be tween the chord and the centre of the circle=[P]let
we have
P=d Sin (C/2)
=40*sin (70/2)
=22.9cm
the perpendicular distance be tween the chord and the centre of the circle is 22.9cm.
(b) Using = 3.142, find the length of the minor arc.
Solution given;
minor arc=[tex]\frac{70}{360}*πd=\frac{7}{36}*3.142*40[/tex]
=24.44cm
the length of the minor arc. is 24.44cm.
B.]In the diagram, XZ is a diameter of the cir cle XYZW, with centre O and radius 15/2 cm.
If XY = 12 cm, find the area of triangle XYZ.
Solution given:
XY=12cm
XO=15/2cm
XZ=2*15/2=15cm
Now
In right angled triangle XOY [inscribed angle on a diameter is 90°]
By using Pythagoras law
h²=p²+b²
XZ²=XY²+YZ²
15²=12²+YZ²
YZ²=15²-12²
YZ=[tex]\sqrt{81}=9cm[/tex]
:.
base=9cm
perpendicular=12cm
Now
Area of triangle XYZ=½*perpendicular*base
=½*12*9=54cm²
the area of triangle XYZ is 54cm².
Answer:
Question 1a)
d = 40 cm ⇒ r = 20 cm
Let the perpendicular distance is x.
Connecting the center with the chord we obtain a right triangle with hypotenuse of r and leg x with adjacent angle of 70/2 = 35°.
From the given we get:
x/20 = cos 35°x = 20 cos 35°x = 16.383 cm (rounded)b)
The minor arc is 70° and r = 20
The length of the arc is:
s = 2πr*70/360° = 2*3.142*20*7/36 = 24.437 cm (rounded)Question 2Since XZ is diameter, the opposite angle is the right angle, so the triangle XYZ is a right triangle.
r = 15/2 cm ⇒ XZ = d = 2r = 2*15/2 = 15 cmFind the missing side, using Pythagorean:
[tex]YZ = \sqrt{XZ^2 - XY^2} = \sqrt{15^2-12^2} = \sqrt{81} = 9[/tex]The area of the triangle:
A = 1/2*XY*YZ = 1/2*12*9 = 54 cm²Select the correct answer.
What is the value of x in the triangle?
Answer:
The answer is A. 21
Hope it helps.
Step-by-step explanation:
• • •
I'm not sure how to answer this!!
Answer:
I think it's a
Step-by-step explanation:
hsjshbwibs hshhsvsu hshsbsbus
PLEASE HELP 30 POINTS
Find the value of x in the triangle below.
804
155
55°
o
75
80°
Ο Ο
85
Answer:
75°
Step-by-step explanation:
First, we need to know that the interior angle sum of a triangle is always 180°.
Now, to find the missing angle aside from x, we need to complete the sum 180-155=25, seeing 155° lies on a straight line. Remembering the interior angle sum of a triangle is always 180°, it is thus clear that 25+80+x=180. If we complete this equation, x=75.
Hope this helps!
Which is the angle of elevation from C to B?
Answer:
Angle of elevation = ∠4
Step-by-step explanation:
Angle of elevation of a point point from another point is the angle formed between the line joining these points and the horizontal line.
Therefore, angle of elevation of point B from a point C = ∠4
Option with angle 4 will be the answer.
99999+999=????????????????????????????
Answer:
100998 is the answer.
I hope this help u.
Answer:
100998
Step-by-step explanation:
₁ ₁ ₁ ₁ ₁
99999
+ 999
100998
you can also think of it as
99999(+1) + 999(-1)
100000+998
100998
