let 'x' be the number of eggs at the beginning
'y' be the number of eggs left
you're given that 14 eggs were left and that 30% was used therefore using that idea we can conclude that 14 is (100%-30%) of the total number of eggs or it is 70%
so we'll have the expression as:
14 = 0.70x
x = 14/0.70
x = 20 eggs
since there are 20 eggs at the beginning then you'll have the number of eggs left as,
y = x - 14
y = 20 - 14
y = 6 eggs
