Question

A sum of rs 700 is to be used to give 7 cash prizes to students of a school for their overall academic performance. if each prize is rs 20 less than precedding prize find the value of each of the prize

Answer 1

let 1st prize be x

then, x+x-20+x-40+x-60+x-80+x-100+x-120=700

7x-420=700

7x=700+420

x=1120/7=160

therefore, value of each prize is 160, 140, 120, 100, 80, 60, 40 respectively.

Answer 2

Answer:

Let the cost of 1st prize be P.

Cost of 2nd prize = P − 20

And cost of 3rd prize = P − 40

It can be observed that the cost of these prizes are in an A.P. having

common difference as −20 and first term as P.

a = P and d = −20

Given that, S7 = 700

7/2[2a+(7-1) d] = 700

a + 3(−20) = 100

a − 60 = 100

a = 160

Therefore, the value of each of the prizes was Rs 160, Rs 140, Rs 120,

Rs 100, Rs 80, Rs 60, and Rs 40.

please please mark my answer as brainlist.