How many terms of the ap 17 15 13


Asked by admin @ in Math viewed by 275 People


How many terms of the ap 17,15,13,........must be added to get the sum 72? Explain the double answer

Answered by admin @



Heya ...

The common difference of this arithmetic progression is -2, then
:
72 = (n/2) * (2a + (n-1)d), where a is the first term, n is the number of terms and d is the common difference
:
72 = (n/2) * ( (2*17) + (n-1)*(-2) )
:
72 = (n/2) * ( 34 -2n + 2)
:
144 = n * ( 34 -2n + 2)
:
144 = 36n -2n^2
:
2n^2 -36n +144 = 0
:
n^2 -18n +72 = 0
:
(n - 12) * (n - 6) = 0

Hope it helps u...!
#bipasha

Similar Questions

Which of the following best describes the long-term impact of using a renewable energy source?

Asked by maham237 @ in Biology viewed by 425 persons

Which of the following best describes the long-term impact of using a renewable energy source? Natural gas causes air pollution when burned. Nuclear power produces harmful radiation. Biomass releases greenhouse …

How many solutions will this system of equations have? y = −3.5x − 3.5 y = −3.5x + 3.5

Asked by maham237 @ in Mathematics viewed by 373 persons

how many solutions will this system of equations have? y = −3.5x − 3.5 y = −3.5x 3.5 no solution infinite solutions one solution two solutions

How many terms of the ap 9 17

Asked by admin @ in Math viewed by 319 persons

How many terms of the AP: 9,17,25,.......... must be taken so that their sum is 636

How many terms of ap 9 17 25

Asked by admin @ in Math viewed by 277 persons

How many terms of the AP: 9,17,25,.......... must be taken so that their sum is 636

How many terms of an ap 9 17 25

Asked by admin @ in Math viewed by 303 persons

How many terms of the AP: 9,17,25,.......... must be taken so that their sum is 636

How many terms of the ap 9 17 25

Asked by admin @ in Math viewed by 270 persons

How many terms of the AP: 9,17,25,.......... must be taken so that their sum is 636

What is the f of x over the g of x when f(x) = − 2x3 + x2 + 16x − 15 and g(x) = x + 3?

Asked by maham237 @ in Mathematics viewed by 340 persons

What is the f of x over the g of x when f(x) = − 2x3 + x2 + 16x − 15 and g(x) = x + 3? −2x2 − …

Which of the following is a zero for the function f(x) = (x − 15)(x + 1)(x − 10)?

Asked by maham237 @ in Mathematics viewed by 375 persons

Which of the following is a zero for the function f(x) = (x − 15)(x + 1)(x − 10)? X=-15 X=-10 X=1 X=15

Make a box and whisker plot of the data. 24,18,29,21, 16,23,13,11

Asked by maham237 @ in Mathematics viewed by 288 persons

Make a box and whisker plot of the data 24,18,29,21,16,23,13,11

In circle a, ∠bae ≅ ∠dae. what is the length of be? 14 units 17 units 27 units 34 units

Asked by maham237 @ in Mathematics viewed by 516 persons

In circle A, ∠BAE ≅ ∠DAE. Circle A is shown. Line segments A B, A E, and A D are radii. Lines are drawn from point B to point E …

Which is a solution to (x − 2)(x + 10) = 13? x = 3 x = 8 x = 10 x = 11

Asked by maham237 @ in Mathematics viewed by 395 persons

Which is a solution to (x − 2)(x + 10) = 13? x = 3 x = 8 x = 10 x = 11

Most viewed questions in Math


What is the value of x in the expression

Asked by admin @ in Math viewed by 15179 persons


Shubham is facing south and moves 30 km

Asked by admin @ in Math viewed by 12991 persons


Prachi excellence in mathematics class 7 solutions pdf free download

Asked by admin @ in Math viewed by 12053 persons



Oxford new enjoying mathematics class 7 solutions chapter 1

Asked by admin @ in Math viewed by 11530 persons


Survey of various types of bank accounts icse project

Asked by admin @ in Math viewed by 11513 persons


The town of p is located at point x

Asked by admin @ in Math viewed by 11364 persons



A clock gains 4 minutes after every 4 minutes

Asked by admin @ in Math viewed by 10178 persons


Running a tuck shop or canteen maths project pdf

Asked by admin @ in Math viewed by 9394 persons


Paul is sixteenth from the front of the row

Asked by admin @ in Math viewed by 9356 persons



The average weight of 20 teachers is 80 kg

Asked by admin @ in Math viewed by 7528 persons


The number 567 xy is completely divisible by 30

Asked by admin @ in Math viewed by 7407 persons


In a row of friends tiya occupies fifteenth place

Asked by admin @ in Math viewed by 7210 persons



What would $ mean if fat is coded as

Asked by admin @ in Math viewed by 5280 persons


Consider a 3 digit integer x with distinct digits

Asked by admin @ in Math viewed by 4808 persons


Rahul went to his mother's mother in law

Asked by admin @ in Math viewed by 4185 persons