Question

the average of some natural numbers is 15 if 30 is added to first number and 5 is subtracted from the last number the average becomes 17.5 then the number of natural number is?​

Answer 1

Answer:

$x \div y = 15$

$(x1 + x2 + x3.....xn + 30 - 5) \div y$

$(x1 + x2 + x3 + ......xn) \div y +( 25 \div y) = 17.5$

$(15) + 25 \div y = 17.5$

$25 \div y = 2.5$

$y = 2.5 \div 25 = 25 \div 250 = 0.1$

therefore y=0.1