length of pipe= 30m
Inside dia. = 1.2m
Outside dia. = 1.8m
Volume of concrete= (outside dia. - inside dia.)h
V= (pi)
v= [(3.14*0.9*0.9)-(3.14*0.6*0.6)]30
v= (3.3534-1.1304)30
v=(2.233)30 = 66.690m cube
since it's volume the answer 66.690 is in cubic meters.
<h2>Time taken by Helga to wax the car is 72 minutes</h2>
Step-by-step explanation:
Let w be the work of waxing.
Rosita can wax her car in 2 hours or 120 minutes.
Time taken by Rosita = 120 minutes

Let time taken by Helga be t,

When she works together with Helga, they can wax the car in 45 minutes.
We have

Time taken by Helga to wax the car is 72 minutes
Answer:
step 1. 6x2=12 first place way
step 2. 12×2=24
step 3. 24+6=30 second place way