Question

After deducting 60% from a certain number and then deducting 15% from the remainder, 1428 is left. What was the initial number?

Answer 1

Let the initial number be x.

Deduction by 60% means = x - 60 % of x

                                            = x - $\frac{60x}{100}$

                                             = $\frac{100x - 60 x}{100}$

                                              = $\frac{40x}{100}$

   Now , if we deduct 15% from remaining number we get 1428.

 →  $=\frac{40x}{100} - \frac{40x}{100}\times \frac{15x}{100} \\=\frac{40x}{100} - \frac{6x}{100} \\=\frac{34x}{100}$

→   $\frac{34x}{100} = 1428$

→ x =  $\frac{1428 \times 100}{34}$

→ x = 42 × 100

→ x = 4,200    

Initial number = 4,200