Sure, let's translate the sentence and solve for the unknown number step-by-step.
1. Translate the sentence into an equation:
- The sentence states: "The sum of 3, 7, and a number amounts to 15."
- Let's define the unknown number as [tex]\( x \)[/tex].
- The equation representing this sentence is:
[tex]\[
3 + 7 + x = 15
\][/tex]
2. Solve the equation:
- Combine the known numbers on the left side of the equation:
[tex]\[
10 + x = 15
\][/tex]
- Isolate the variable [tex]\( x \)[/tex] by subtracting 10 from both sides of the equation:
[tex]\[
x = 15 - 10
\][/tex]
- Simplify the right side:
[tex]\[
x = 5
\][/tex]
Therefore, the unknown number is 5.
