How do I find the value of 2/5 of 30 mangoes?

Finding a fraction 'of' a quantity means multiplying the fraction by that quantity. So 2/5 of 30 = (2/5) × 30. The easiest order is to divide by the denominator first, then multiply by the numerator. Divide 30 by 5 to find one-fifth: 30 ÷ 5 = 6, so one-fifth of 30 is 6 mangoes. Now multiply by the numerator 2 to get two-fifths: 6 × 2 = 12. So 2/5 of 30 is 12 mangoes. You could also multiply first, 2 × 30 = 60, then divide by 5 to get 60 ÷ 5 = 12, which gives the same answer. Dividing first usually keeps the numbers smaller and easier to handle in your head.