Height of the woman = 5 ft
Rate at which the woman is walking = 7.5 ft/sec
Let us assume the length of the shadow = s
Le us assume the <span>distance of the woman's feet from the base of the streetlight = x
</span>Then
s/5 = (s + x)/12
12s = 5s + 5x
7s = 5x
s = (5/7)x
Now let us differentiate with respect to t
ds/dt = (5/7)(dx/dt)
We already know that dx/dt = 7/2 ft/sec
Then
ds/dt = (5/7) * (7/2)
= (5/2)
= 2.5 ft/sec
From the above deduction, it can be easily concluded that the rate at which the tip of her shadow is moving is 2.5 ft/sec.
Answer:
He received 10 dimes and 15 quarters.
Step-by-step explanation:
Dimes = $0.10
Quarters = $0.25
Variable x = dimes
Variable y = quarters
Create a pair of linear equations:
0.10x + 0.25y = 4.75
x + y = 25
Isolate any variable, using an equation of your choice:
x + y = 25
x = 25 - y
Plug in this new value of x into the other equation:
0.10(25 - y) + 0.25y = 4.75
Use the distributive property:
2.5 - 0.10y + 0.25y = 4.75
Combine like terms:
2.5 + 0.15y = 4.75
Isolate variable y:
0.15y = 2.25
y = 15
Plug in the value of y into any equation:
x + y = 25
x + 15 = 25
Isolate variable x:
x = 10
Answer:
66.6%
Step-by-step explanation:
Step one
given
A coat at a store is originally priced at $54.99
The store marks down the price down to $32.99
Required
the percent decrease
Step two:
the percent decrease= change in price/ old price*100
the percent decrease= 54.99-32.99/54.99*100
the percent decrease= 22/ 32.99*100
the percent decrease= 0.666*100
the percent decrease= 66.6%
Answer:
B. Sometimes I am pretty sure