At an icecream parlor, ice cream cones cost $1.10 and sundaes cost $2.35. One day, the receipts for a total of 172 cones and sundaes were $294.20. How many cones and sundaes were sold?

So we have an interesting problem

represent number of icecream cones as x

represent sundays as y

1.1 times x=cost of icecreams

2.35 times y=cost of sundaes so total cost is

1.1x+2.35x=294.20

total cones=x+y=172

x+y=172

1.1x+2.35y=294.2

multiply second equation by 10

11x+23.5=2942

multipily first equation by - 11

-11x-11y=-1892

add to firest equation

11x+23.5y=2942

-11x-11y=-1892 +

0x+12.5y=1050

12.5y=1050

divide both sides by 12.5

y=84

subsitute 84 for y

x+84=172

subtract 84 from btoh sides

x=88

88 cones were sold

84 sundaes were sold