AlgebraEasy–MediumTwo multiples of a number set equal
Algebra practice question
Seven times a number, plus 3, is equal to five times the same number, plus 11. What is the number?
Answer: 4
Let the number be x: 7x + 3 = 5x + 11. Subtract 5x: 2x + 3 = 11. Subtract 3: 2x = 8, x = 4.
Common wrong answers
- If you answered 2
- 2 comes from 7x + 3 = 5x + 11 with 12x = 8 or a similar slip; 7x − 5x = 2x.
- If you answered 7
- 7 comes from 2x = 14, adding the constants instead of subtracting.
- If you answered 8
- 8 is 2x, one step short.
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