Step-by-step explanation:
It will take 42.35 minutes to weed the garden together.
Why?
To solve the problem, we need to use the given information about the rate for both Laura and her husband. We know that she can weed the garden in 1 hour and 20 minutes (80 minutes) and her husband can weed it in 1 hour and 30 minutes (90 minutes), so we need to combine both's work and calculate how much time it will take to weed the garden together.
So, calculating we have:
Laura's rate:
\frac{1garden}{80minutes}
80minutes
1garden
Husband's rate:
\frac{1garden}{90minutes}
90minutes
1garden
Now, writing the equation we have:
Laura'sRate+Husband'sRate=CombinedRateLaura
′
sRate+Husband
′
sRate=CombinedRate
\frac{1}{80}+\frac{1}{90}=\frac{1}{time}
80
1
+
90
1
=
time
1
\frac{1*90+1*80}{7200}=\frac{1}{time}
7200
1∗90+1∗80
=
time
1
\frac{170}{7200}=\frac{1}{time}
7200
170
=
time
1
\frac{17}{720}=\frac{11}{time}
720
17
=
time
11
\frac{17}{720}=\frac{1}{time}
720
17
=
time
1
\frac{17}{720}*time=1
720
17
∗time=1
time=1*\frac{720}{17}=42.35time=1∗
17
720
=42.35
Hence, we have that it will take 42.35 minutes to weed the garden working together.
