Answer:
Explanation:
To find the number that Grace thought:
We'll represent the unknown number as "x."
"Added 7": This can be represented as (x + 7).
"Multiplied by 3": This becomes 3 * (x + 7).
"Took away 5": This is represented as 3 * (x + 7) - 5.
"Divided by 4": This gives (3 * (x + 7) - 5) / 4.
"To give an answer of 7": The equation is (3 * (x + 7) - 5) / 4 = 7.
Now we can solve for x:
(3 * (x + 7) - 5) / 4 = 7
Multiply both sides by 4 to eliminate the denominator:
3 * (x + 7) - 5 = 28
Simplify the left side:
3x + 21 - 5 = 28
Combine like terms:
3x + 16 = 28
Subtract 16 from both sides:
3x = 12
Divide both sides by 3:
x = 4
Therefore, the number that Grace thought of is 4.