Question

21 is 70% of what number

Answer 1

Answer:

30 is the number which gives 21 when taking 70% of 30 i.e  70% of 30 is 21

Step-by-step explanation:

Let x be the number which gives 21 when taking 70% of the number x.

We have to find the value of x.

∴ According to question

$70\% of x=21$

⇒ $\frac{70}{100}\times x=21$

⇒ $x=\frac{21\times 100}{70}$

⇒ $x=30$

Hence, 30 is the number which gives 21 when taking 70% of 30 i.e we can say 70% of 30 is 21

Answer 2

if the number is X, then 70 % of the number X has a value of 21.
then we can write it as an equation as follows
X * 70 % = 21
since 70% is equivalent to 0.7
                                                             
X * 0.7 = 21
                                                                     
X = 21 / 0.7
                                                                         
X = 30
                                                                     
therefore number is 30