Question 914174
Mr.Man has a sum of money to buy fruits.  let the amount be m



He can buy n mangoes at €1.60 each and have €0.80 left.

m-1.60n=0.80.................(1)

 Alternatively, he can buy (n+10) apples at €0.70 each and have €0.10 left 

m-0.70(n+10)=0.10

m-0.70n-7=0.10
m-0.70n=7.10..................(2)

1.00	m		-1.60	n	=	0.80	.............1	
								
1.00	m		-0.70	n	=	7.10	.............2	
Eliminate	y							
multiply (1)by		-0.70						
Multiply (2) by		1.60						
-0.70	m		1.12	n	=	-0.56		
1.60	m		-1.12	n	=	11.36		
Add the two equations								
0.90	m				=	10.80		
/	0.90							
m	=	12.00		



12-1.6*3 = 7.2

Apple costs 0.70

Number of apples = 7.2/0.7  
0.7*10=7

he can buy 10 apples and will have 0.2 Euro left