Answer:
10
Step-by-step explanation:
Given:it takes them 1.5 hours to plant one acre.
So, in order to plant all 15 acres it would take
15/1.5 = 10 hours
To
understand this picture 2 cones that are stacked one on top of
another. A double-napped cone is created when a generator is rotated
about a fixed vertical axis. A line is created when the cone is cut
by a plane containing the generator. Please see the attachment to
help you understand this.
I
hope this helps, Regards.
9514 1404 393
Answer:
A: 66/21
E: 22/7
Step-by-step explanation:
The offered choices reduce to 3 1/7 or to 3. The best approximations of those given are the ones that reduce to 3 1/7.
A: 66/21 = 22/7 = 3 1/7
B: 60/20 = 3
C: 21/7 = 3
D: 45/15 = 3
E: 22/7 = 3 1/7
___
<em>Comment on pi approximations</em>
The ratio 22/7 differs from π by about 0.04%. A better approximation is 355/113, which differs from π by about 0.000008%. The approximation 3.14 differs from π by about 0.05%.
The paraboloid meets the x-y plane when x²+y²=9. A circle of radius 3, centre origin.
<span>Use cylindrical coordinates (r,θ,z) so paraboloid becomes z = 9−r² and f = 5r²z. </span>
<span>If F is the mean of f over the region R then F ∫ (R)dV = ∫ (R)fdV </span>
<span>∫ (R)dV = ∫∫∫ [θ=0,2π, r=0,3, z=0,9−r²] rdrdθdz </span>
<span>= ∫∫ [θ=0,2π, r=0,3] r(9−r²)drdθ = ∫ [θ=0,2π] { (9/2)3² − (1/4)3⁴} dθ = 81π/2 </span>
<span>∫ (R)fdV = ∫∫∫ [θ=0,2π, r=0,3, z=0,9−r²] 5r²z.rdrdθdz </span>
<span>= 5∫∫ [θ=0,2π, r=0,3] ½r³{ (9−r²)² − 0 } drdθ </span>
<span>= (5/2)∫∫ [θ=0,2π, r=0,3] { 81r³ − 18r⁵ + r⁷} drdθ </span>
<span>= (5/2)∫ [θ=0,2π] { (81/4)3⁴− (3)3⁶+ (1/8)3⁸} dθ = 10935π/8 </span>
<span>∴ F = 10935π/8 ÷ 81π/2 = 135/4</span>
Since the number of days in July and in August is the same, there is no need to work out on the total number per month.
The mean number of people per day in August = 160 + 20 = 180
Answer: 180
