ASVAB Arithmetic Reasoning Practice Test

To determine the expression for an unknown number increased by 7, we start by defining the unknown number as \( x \). The phrase "increased by" indicates that we will add a certain number to \( x \) – in this case, 7.

When we say "the unknown number increased by 7," it mathematically translates to adding 7 to \( x \). Therefore, the correct expression becomes \( x + 7 \).

This aligns perfectly with the answer choice provided, as it directly reflects the operation described in the question: taking the unknown number \( x \) and adding 7 to it. Other expressions do not accurately depict this operation. For instance, subtracting from \( x \) or changing the order of addition would not capture the intended meaning of "increased by." Thus, the expression \( x + 7 \) is indeed the appropriate representation of the problem statement.