Answer:
The principal he borrowed is $1500
Step-by-step explanation:
Let's assume principal he borrowed as P
now, we can use formula
where
SI is simple interest
r is interest rate
t is time in years
we are given
r=4%
SI=240
t=4
now, we can plug this value
now, we can solve for P
So,
The principal he borrowed is $1500. Hope this helps, and mark me as brainlest!
Problem 9
r+h = 9
SA = 2*pi*r^2 + 2*pi*r*h = 54pi
2*pi*r^2 + 2*pi*r*h = 54pi
2pi*r(r + h) = 54pi
r(r+h) = 27
r(9) = 27
9r = 27
r = 27/9
r = 3
r+h = 9
h = 9-r
h = 9-3
h = 6
Answers: r = 3 and h = 6 are the radius and height respectively.
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Problem 10
d = diameter = 68 mm
r = radius = d/2 = 68/2 = 34 mm
SA = surface area of a sphere
SA = 4*pi*r^2
SA = 4*pi*34^2
SA = 4264pi
Answer: 4264pi square mm
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Problem 11
Plug V = 3000 into the sphere volume formula and isolate r.
V = (4/3)pi*r^3
3000 = (4/3)pi*r^3
(4/3)pi*r^3 = 3000
4pi*r^3 = 3*3000
4pi*r^3 = 9000
r^3 = 9000/(4pi)
r = cube root( 9000/(4pi) )
r = ( 9000/(4pi) )^(1/3)
r = 8.947002 approximately
Now we can determine the surface area of this sphere.
SA = 4pi*r^2
SA = 4*pi*( 8.947002 )^2
SA = 1005.923451
Answer: 1005.923451 square feet approximately
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Problem 12
We'll follow the same idea as problem 11, but in reverse.
SA = 4*pi*r^2
400pi = 4pi*r^2
r^2 = (400pi)/(4pi)
r^2 = 100
r = sqrt(100)
r = 10
Luckily we get a nice whole number for the radius r. Use it to find the volume.
V = (4/3)*pi*r^3
V = (4/3)*pi*10^3
V = (4000/3)pi
Answer: (4000/3)pi cubic inches exactly
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Problem 13
The diagram is missing. I don't have enough info to be able to answer.
A "solution" would be a set of three numbers ... for Q, a, and c ... that
would make the equation a true statement.
If you only have one equation, then there are an infinite number of triplets
that could do it. For example, with the single equation in this question,
(Q, a, c) could be (13, 1, 2) and they could also be (16, 2, 1).
There are infinite possibilities with one equation.
In order to have a unique solution ... three definite numbers for Q, a, and c ...
you would need three equations.
Answer:
y = 36
Step-by-step explanation:
so there directly proportional..so lets make a proportion
if y = 9 when x = 5, what is the value of y when x = 20...
5 20
------ = ----- (cross multiply)
9 y
(5)(y) = (20)(9)
5y = 180
y = 180/5
y = 36 <=== so when x = 20, y = 36
Answer:
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