75% of 140 = 0.75 x 140 = 105 ... 105 ÷ 0.75 = 140
Or
3/4 x 140 = (300 + (3x40)) ÷ 4
(300÷4) + ((3x40)÷4) = 75 + (3x10) = 75 +30 = 105
You could say :-
75/100 x 140 = 75 x 140/100
= 75 x 1.4 = 75 + (4/10 x 75) = 75 + (4 x 75/10) = 75 + (4 x 7.5)
=75 + 30 = 105
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