Skip to main contentSkip to solution

A factory kept increasing its output by the same percentage every year. Find the percentage if it is known that the output has doubled in the last two years. (assume 2=1.4142\sqrt{2} = 1.4142)

Solution

✅ Correct Option: 1

Let rr = the annual growth rate (as a decimal)

Let initial output = 100 units

After 2 years: Output = 100×(1+r)2100 \times (1 + r)^2


Since output doubles in 2 years:

100×(1+r)2=2×100100 \times (1 + r)^2 = 2 \times 100

(1+r)2=2(1 + r)^2 = 2


1+r=21 + r = \sqrt{2}


Using the given value 2=1.4142\sqrt{2} = 1.4142:

1+r=1.41421 + r = 1.4142

r=1.4142−1r = 1.4142 - 1

r=0.4142r = 0.4142


r=0.4142=41.42%r = 0.4142 = 41.42\%

The factory increases its output by 41.42% every year.

Keyboard Shortcuts

  • Left arrow: Previous question
  • Right arrow: Next question
  • S key: Jump to solution
  • Q key: Jump to question