# Mensuration

• December 9th 2010, 07:26 AM
rn5a
Mensuration

A field is 150 m long & 100 m wide. A plot (outside the field) 50 m long & 30 m wide is dug to a depth of 8 m & the earth taken out from the plot is spread evenly in the field. By how much is the level of the field raised?

Thanks,

Ron
• December 9th 2010, 07:32 AM
BariMutation
First, as I'm sure you knew, you have to find the volume of the plot. Notice how you have a 3D object (being the plot), and a 2D object (being the field). Essentially, you need to turn that field into a 3D object by adding an unknown height. So, you will have a box 150 wide, 100 long, and x deep. You are now left with this equation:

$(150)(100)(x) =$ volume of plot
• December 9th 2010, 07:58 AM
rn5a

150x100xh=50x30x8
15000h=12000
h=12000/15000
h=0.8m (or 80 cm)

Am I correct?

Thanks,

Ron
• December 9th 2010, 08:05 AM
BariMutation
Yep, completely correct :)