Question

when a number is decreased by 30% of itself, the result is 28

Answer 1

let the no is x . so by cond, x - (30% off x)= 28 => x - (30*x / 100 )= 28 => x - (30x /100)= 28 => x - 3x /10=28 => (110x - 3x)=28 => 7x = 28 => x = 28/7=4

Answer 2

let nub be x

then decrease value 100-30=70

hence.. 70x/100 =28

 

x = 28 *100/70

x = 40