1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

# Tick (✓) the correct answer: A alone can do a piece of work in 10 days and B alone can do it in 15 days. In how many days will A and B together do the same work? (a) 5 days (b) 6 days (c) 8 days (d) 9 days

Open in App
Solution

## (b) 6 days ​$\mathrm{A}\mathrm{can}\mathrm{do}\mathrm{a}\mathrm{work}\mathrm{in}10\mathrm{days}.\phantom{\rule{0ex}{0ex}}\mathrm{A}\text{'}\mathrm{s}1\mathrm{day}\mathrm{work}=\frac{1}{10}\phantom{\rule{0ex}{0ex}}\phantom{\rule{0ex}{0ex}}\mathrm{B}\mathrm{can}\mathrm{do}\mathrm{a}\mathrm{work}\mathrm{in}15\mathrm{days}.\phantom{\rule{0ex}{0ex}}\mathrm{B}\text{'}\mathrm{s}1\mathrm{day}\mathrm{work}=\frac{1}{15}\phantom{\rule{0ex}{0ex}}\phantom{\rule{0ex}{0ex}}\left(\mathrm{A}+\mathrm{B}\right)\text{'}\mathrm{s}1\mathrm{day}\mathrm{work}=\frac{1}{10}+\frac{1}{15}=\frac{5}{30}=\frac{1}{6}\phantom{\rule{0ex}{0ex}}\phantom{\rule{0ex}{0ex}}\text{A and B}\mathrm{together}\mathrm{will}\mathrm{take}6\mathrm{days}\mathrm{to}\mathrm{complete}\mathrm{the}\mathrm{work}.$

Suggest Corrections
8
Join BYJU'S Learning Program
Related Videos
Algebraic Solution
MATHEMATICS
Watch in App
Join BYJU'S Learning Program