the average age of an adult class is 40 years . 2 new students with an avg age of 32 years join the class . therefore decreasing the average by 4 year . find what was the original strength of class ?
"let original strength = y then , 40 y + 2 x 32 = ( y + 2 ) x 36 â ‡ ’ 40 y + 64 = 36 y + 72 â ‡ ’ 4 y = 8 â ˆ ´ y = 2 d"
divide(subtract(multiply(2, subtract(40, 4)), multiply(2, 32)), 4)