A man spends 2/5 of his income on house rent, 3/10 on food and 1/8 on conveyance. If he has ₹ 2800 left with him, find his expenditure on food and conveyance together.

Hint 1.
Let consider the monthly income = x ;
Amount spend on House rent = 2x/5;
Amount spend on food = 3x/10;
Amount spend on conveyance = x/8;
After Expenditure , The left amount = 2800;
According to Question;
x - ( 2x/5 + 3x/10 + x/8 ) = 2800 ;
x- ((16x + 12x + 5x)/40) = 2800 ;
x - 33x/40 = 2800 ;
(40x - 33x)40 = 2800 ;
7x/40 = 2800 ;
7x = 2800 x 40 ;
x = 2800 x 40/7 ;
x = 400 x 40 ;
x = 16000 ;
Expenditure on food = 3x/10 = 3 x 16000 /10= ? 4800
Expenditure on conveyance = x/8 = 1 x 16000/8 = ? 2000
? Expenditure on food and conveyance together
=? (4800 + 2000) = ? 6800
Solution 2 .
part of income left
= 1 - (2/5 + 3/10 + 1/8 )
=1- (16 + 12 + 5/40)
= 1- 33/40 = 40 - 33/40 = 7 /40
Let the monthly income = x
According to the question,
7/40 x = 2800
∴ x = 2800 x 40/7
= 400 x 40 = ₹ 16000
Expenditure on food = 3/10 x 16000 = ₹ 4800
Expenditure on conveyance = 1/8 x 16000 = ₹ 2000
∴ Expenditure on food and conveyance together
=₹ (4800 + 2000) = ₹ 6800