Question

3 times a number is equal to five times the difference of the number and 4. what is the number?​

Answer 1

3x = 5(x-4)

3x = 5x - 20

3x = 20

x = 10

Answer 2

Let's consider that $a$ be the unknown number.

As it is given that, 3 times a number is equal to five times the difference of the number and 4. So our equation become like this,

$\implies 3a = 5(a - 4)$

Now, solving the above equation to get the value of unknown number.

$\implies 3a = 5(a - 4) \\ \\ \implies 3a = 5a - 20 \\ \\ \implies 3a - 5a = -20 \\ \\ \implies -2a = -20 \\ \\ \implies 2a = 20 \\ \\ \implies\boxed{a = 10}$

Hence, the unknown number is 10.