Pythagorean Theorem:
a^2 + b^2 = c^2
10. 144 + 196 = 340
Yes, it is a right triangle
11. 256 + 361 does not equal 684 so it is not a right triangle
30% off an item would make that item valued at 70% of its original price
94 times 0.7 = 65.8
$65.80
They will have to buy all three items again in 9 years
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