school
Acemy

Linear Equations in One Variable

SAT Math· difficulty 4/5

Worker A can complete a job in xx hours and worker B in x+2x + 2 hours. Together they finish in 2.42.4 hours. What is xx?

  • A

    4

    check_circle
  • B

    3

  • C

    6

  • D

    5

Explanation

1x+1x+2=12.4\frac{1}{x} + \frac{1}{x+2} = \frac{1}{2.4}. Try x=4x = 4: 14+16=512≈0.417\frac{1}{4} + \frac{1}{6} = \frac{5}{12} \approx 0.417. And 12.4≈0.417\frac{1}{2.4} \approx 0.417. Confirmed: x=4x = 4.

Want 10 more like this — adaptive to your weak spots?

Practice 10 like thisarrow_forwardPredict my AP score

Related questions

auto_awesomeAll Toolsquestion_answerHomework Q&Amenu_bookAP & SAT PreptimelineLearn Mode