Albert bought a number of apples. 4/5 of the green apples was equal to 3/4 of the red apples. He sold 105 green apples and 102 red apples. After that, the ratio of the number of green apples to the number of red apples became 5:6. How many apples did Albert have left in the end?
4/5 g = 3/4 r this is given.
re-arrange to g = 15/16 r
then
(g - 105 ) / (r-102) = 5/6
g-105 = 5/6 (r-102) sub in the red equation
15/16 r - 105 = 5/6 r - 85
r = 192 then using the red equation again g = 180 for a total = 372 apples originally
then he sold 105 + 102
372 - ( 105+102) = 165 aplles left