Area of a trapezoid = a+b+c x h
10 + 5 +12 = 27 x h
27h = 27 x 1.5 = 40.5
<span> (y2-y1) that's the formula </span>
You have the right one selected.
The answer is 2:1
To find this take each side of ABC and its corresponding side on DEF, then simplify. You can treat ratios just like fractions, so simplify them in the same way.
20:10 becomes 2:1
12:6 becomes 2:1
16:8 becomes 2:1
Question a:
Mass = Density × Volume
Density = Mass/Volume
Volume of the tree trunk (the shape of Cylinder) = Area of circular base × height
Volume = [πr²] × h
Volume = [π × 0.25²] × 20
Volume = 3.93 m³
Density = 380 kg/m³
Mass = Density × Volume
Mass = 380 × 3.93
Mass = 1493.4 kg
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Question b)
The growth ring = 4 millimeters = 4÷1000 = 0.004
New diameter = 0.5 + 0.004 = 0.5004
New height = 20 + 0.2 = 20.2
New volume = [πr²] × h
New volume = [π × 0.2502²] × 20.2
New volume = 3.97 m³
