The formula for volume is
volume= length * width *height
if there are 1,305 gallons and 7.5 gallons per cubic foot
than 1,305/7.5= 174 cubic feet
174 cubic feet= 14.5*12*h
174= 174h
divide both sides by 174
1=h
the pond is 1 foot in height
Here is one example of when you would use the friendly number strategy to subtract.
42 - 18
We will turn the 18 into a friendly number, which is going to be 20.
(42 + 2) - (18 + 3)
44 - 20
Now it is easier to subtract 44 - 20 than it is 42 -18. With 42 - 18 we would have to barrow whereas with 44 -20 we do not have to barrow and we can do it in our head easier and makes it faster.
Hope this helps.
In the second problem, because 3 is not large enough to subtract 6 from, change 4 to 3 and add 1 before 3 to get 13-6.
God bless!!! xx
Answer:
x is 7 in this question...