Question

Barbara is thinking of a number. If you multiply it by 5, then subtract 4, then add 6,

and finally divide by 2, the result is 51.
What number is Barbara thinking of?

Help please!!

Answer 1

Answer is 20

Explanation:

Let's say the number is x

So x × 5 - 4 + 6 ÷ 2= 51

We do backwards solving meaning everything is opposite so 51× 2= 102

102 - 6 = 96

96 +4 = 100

100 ÷5= 20

So the number is 20

-------------------------------------

You can even check you answer:

20× 5= 100

100-4=96

96+6= 102

102÷2= 51

Answer 2

20

Explanation:

start of backwards with 51

instead of divide, multiply: 51 * 2 = 102

instead of addition, use subtraction: 102-6=96

vice versa: 96 + 4 = 100

instead of multiply, divide: 100/5 = 20

and you get 20!!