Question

. Ingrid can decorate the hedge of a big park in 12
days. Her son Sven can do it in 9 days. Both of them
start working and after 3 days, Sven breaks his leg.
How much more time will be taken by Ingrid to
decorate the hedge?​

Answer 1

Answer:

Ingrid takes 5 days more to decorate the hedge

Step-by-step explanation:

Ingrid can decorate hedge in 12 days

Therefore, in 1 day Ingrid does work = 1/12

Similarly, in 1 day Sven does work = 1/9

In three days both Ingrid and Sven did

= $3(\frac{1}{12}+\frac{1}{9})$ work

= $3(\frac{3+4}{36})$ work

= $\frac{7}{12}$ work

work left = $1-\frac{7}{12}$ = $\frac{5}{12}$

Let ingrid takes n days to complete 5/12 work

Therefore

$\frac{n}{12}=\frac{5}{12}$

$\implies n=5$

Therefore, Ingrid takes 5 more days to decorate the hedge