7x = 3.5; what is x?

7x = 3.5; what is x?

• A. 0.25
• B. 0.5
• C. 1
• D. -0.5

Answer: (B)

To find x, undo the multiplication by 7. If 7x equals 3.5, then x is 3.5 divided by 7. Calculating 3.5 ÷ 7 gives 0.5, so x = 0.5. You can check by multiplying back: 7 × 0.5 = 3.5, which matches. Other options don’t fit because they would give different results when multiplied by 7—for example, 7 × 0.25 = 1.75, 7 × 1 = 7, and 7 × -0.5 = -3.5.

To find x, undo the multiplication by 7. If 7x equals 3.5, then x is 3.5 divided by 7. Calculating 3.5 ÷ 7 gives 0.5, so x = 0.5. You can check by multiplying back: 7 × 0.5 = 3.5, which matches. Other options don’t fit because they would give different results when multiplied by 7—for example, 7 × 0.25 = 1.75, 7 × 1 = 7, and 7 × -0.5 = -3.5.