Question

Suppose you got 8 mangoes and 3 apples for $18 and 3 mangoes and 5 apples for $14.50.

Answer 1

Let x = cost of mango
y = c of apples 
8x+3y=18.
3x+5y=14.5 

 
24x+9y=54
24x+40y=116
multiplying them with 3 and 8 resectively. 
subtract one from the other we get 
40y-9y=116-54 
31y=62 
y=2.
cost of apple=2$  per apple
8x+3y=18,
 8x+3(2)=18.
8x=12. x=12/8=1.5 
cost of mango i= 1.5 $ per mango
hope this helps