Answer:
6 inches
Step-by-step explanation:
The perimeter of a triangle is a + b + c
Where, a, b, c are the length of the 3 sides of the triangle ;
Using the ruler ;
a = 1.5
b = 2
c = 2.5
Therefore,
a + b + c
1.5 + 2 + 2.5
= 6 in
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.
35% off means that now it costs 100%-35%=65% of the original price
<span>£78 ---- 65%
x------100%
x=78*100/65=120</span>£<span>
or
part/whole=0.65
78/whole=0.65
whole =78/0.65 =120 </span>£