Answer:
It's D because 2y and 0.5x both have a vrible besilde it .
An architect built a scale model of a shopping mall. On the model, a circular fountain is
20
20 inches tall and
22.5
22.5 inches in diameter. The actual fountain is to be
8
8 feet tall. What will be the diameter of the fountain? (A)
7.1
7.1 feet (B)
9
9 feet (C)
7
7 feet (D)
10.5
10.5 feet
Explanation
Verified
Step 1
1 of 2
Given a circular fountain is 20
i
n
c
h
e
s
inches tall and 22.5 inches in diameter.
Writing above scale as fraction
Height
Diameter
=
20
22.5
Diameter
Height
=
22.5
20
Now given the fact that actual fountain is 8
f
e
e
t
feet i.e 96
i
n
c
h
e
s
inches tall and let its diameter be
x
x
i
n
c
h
e
s
inches, therefore
20
22.5
=
96
x
22.5
20
=
x
96
4 unknowns needs 4 equations. I'll call the unknown numbers a,b,c,d in that order left to right.
4 + a = b
a + b = c
b + c = d
c + d = 67
let's use substitution to get rid to combine equations and get rid of variables.
If a + b = c then a = c - b
4 + (c - b) = b
4 + c = 2b
If b + c = d then b = d - c
4 + c = 2(d - c)
4 + c = 2d - 2c
4 + 3c = 2d
then we have c + d = 67 so c = 67 - d
4 + 3(67 - d) = 2d
4 + 201 - 3d = 2d
205 = 5d
d = 41
Should be easy now, subtract backwards.
67 - 41 = 26
41 - 26 = 15
26 - 15 = 11
15 - 11 = 4
4, 11, 15, 26, 41, 67
the awnser is c 10 miles per hour
Answer:
B
Step-by-step explanation:
Not all of the pairs represent the same ratio