Exponential decay is given by the equation
F = P(1 - r)^t
0.5 = 1(1 - 0.092)^t
0.5 = (0.908)^t
log 0.5 = log (0.908)^t
log 0.5 = t * log 0.908
t = (log 0.5)/(log 0.908)
t = 7.18
Answer: 7.2 years
B + 24 + 7b + 4b = 180
12b + 24 = 180
12b = 156
b = 13
A.
If:
j - the price of a glass of juice
p - the price of a pancake special
Then:
3j + 5p = 7.60
j + 2p = 2.90
b.
If:
j + 2p = 2.90
Then:
j = 2.90 - 2p
We can substite j in the first equation.
<span>If:
3j + 5p = 7.60
</span><span>j = 2.90 - 2p
</span>Then:
3×(2.90-2p) + 5p = 7.60
8.70 - 6p + 5p = 7.60
8.70 - p = 7.60
⇒ p = 8.70 - 7.60
⇒ p = 1.10
If:
<span>j = 2.90 - 2p
</span><span>p = 1.10
</span>Then:
j = 2.90 - 2×1.10
j = 2.90 - 2.20
j = 0.70
Thus, the price of a glass of juice is $0.70 and <span>the price of a pancake special is $1.10.
c.
If:
p = 1.10
j = 0.70
Then:
j + p = 1.10 + 0.70 = 1.80
Thus, </span><span>the bill for 1 glass of orange juice and 1 pancake special is $1.80.</span>
Whole, integer, and rational
A circle is a two-dimensional line that forms a closed loop, where every point on that loop is an equal distance from the center.[1] The circumference (C) of a circle is its perimeter, or the distance around it.[2] The area (A) of a circle is how much space the circle takes up or the region enclosed by the circle.[3] Both area and perimeter can be calculated with simple formulas using the radius or diameter of the circle and the value of pi.