Question

a boy has an average of 50 in 5 test. how much should he get in next test to have average of 70?
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Answer 1

Step-by-step explanation:

ANSWER IS 170.

SUM OF FIRST FIVE TEST = 50 * 5 = 250 .

LET HE GOT X MARKS IN THE NEXT TEST

THEREFORE,

$\frac{250 + x}{6} = 70 \\ \\ \\ \\ x + 250 = 420 \\ \\ x = 420 - 250 \\ \\ x = 170.$

Answer 2

Answer:

Step-by-step explanation:

average of 50 in 5 tests, we have to find the score of 6th test so that average becomes 70

so, use the formula for average:

average= sum of all scores/number of tests

70 = 50+ X / 6

70 * 6 = 50 + X

420 - 50 = X

370 = X

So the boy has to score 370 marks in 6th test to have an average of 70.