Translate into mathematical expressions and find the number?

Question

Translate into mathematical expressions and Find the number
Enter numeric answers. Use x as variable.
Three less than two-thirds of a number is three
>2 /3 x - 3 = 3
>2/3 x - 3 + 3 = 3 + 3
>2/ 3 x / 2/ 3 = 6 / 2/3
> x = 9 numeric answer
>
>The ratio of a number and five is two.
>x / 5 = 2
> x = 2 X 5
> x = 10
>
>The total of three less than a number and seven is ten
>x - 3 + 7 = 10
>x + 4 = 10
>x + 4 - 4 = 10 - 4
> x + 0 = 6
> x = 6 answer
>
>The product of two and three less than a number
>is a negative four.
>2(x - 3) = -4
>2x - (2 X 3) = -4
>2x - 6 = -4
>2x - 6 + 6 = -4 + 6
>2x - 0 = 2
>2x = 2
>2x / 2 = 2 / 2
> x = 1 numeric answer
>
>The product of three more than twice a number
>and two is fourteen.
>3(2x) + 2 =14
>3 X 2x + 2 = 14
> 6x + 2= 14
> 6x + 2 - 2 = 14 - 2
> 6x = 12
> 6x / 6 = 12 / 6
> x = 2 answer
>Are all these numeric answers correct ? yes or no

Nov 16, 2007 Friday

Answer 1

On the last one, even though the answer is correct, that is by accident, your approach was incorrect. You should have done:
(3 + 2x) * 2 = 14
(3 + 2x) = 14 / 2
3 + 2x = 7
2x = 7 - 3
2x = 4
x = 4 / 2
x = 2

Answer 2

Yes, all are correct. Good work.