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1 vote
I think of a number, double it, then subtract 7. The result is 10.
Find the number.

User Slawekwin
by
5.1k points

2 Answers

2 votes

Answer:

Your number is 8.5 or 17/2

Explanation:

Let's say your number is equal to the variable n.

Then we can set up an equation for this scenario: 2n - 7 = 10

Now, we need to use algebra to solve:

2n - 7 = 10 → add 7 to both sides

2n = 17 → divide both sides by 2

n = 17/2 = 8.5

Thus, the number you were thinking of was 8.5, or 17/2

User Alexandru Puiu
by
5.2k points
4 votes

Answer:

17/2

Explanation:

Work backwards. you have 10, then opposite of subtract 7 is add 7 which gives you 17. then opposite of double is half getting you 8.5 or 17/2

User Fei Yao
by
5.9k points