Question

the average number of icecream cones on monday tuesday and Wednesday in a school were 43, the average for Tuesday Wednesday nd thrusday was 45 for thrusday the sale was 42.Find the sale on monday?

Answer 1

x +y+z = 129
y+z+42 = 135
y+z = 93

x+93 = 129
x = 36

So, sale on monday = 36

Answer 2

x +y+z = 129
y+z+42 = 135
y+z = 93

x+93 = 129 
x = 36

so 36 icecreams will be the average