Answer: She started with $160.
It will take 6 weeks before she has less than half of what she originally invested.
Step-by-step explanation:
If her money is decreasing in value by 11% each week, it means that the rate at which it is decreasing is exponential.
We would apply the formula for exponential decay which is expressed as
A = P(1 - r)^t
Where
A represents the value of the investment after t weeks.
t represents the number of weeks.
P represents the initial value of the investment.
r represents rate of depreciation.
From the information given,
A = $142.40
r = 11% = 11/100 = 0.11
t = 1
Therefore
142.40 = P(1 - 0.11)^1
142.40 = P(0.89)
P = 142.4/0.89
P = 160
For her to have half of what she invested originally, then
80 = 160(0.89)^t
80/160 = (0.89)^t
0.5 = (0.89)^t
Taking log of both sides to base 10
Log 0.5 = log0.89^t = tlog0.89
- 0.3010 = - 0.051t
t = - 0.3010/- 0.051
t = 5.9
Approximately 6 weeks
We can know from the pic
2x+38=90
so, x=26
Answer:
18 pounds = 48 pizzas
18 pounds = 48 pizzas 22.5 pounds = 60 pizzas
18 pounds = 48 pizzas 22.5 pounds = 60 pizzas 27 pounds = 72 pizzas
Step-by-step explanation:
1) because they are ratios you multiply 18 and 8 (18 × 8 = 144) then you divide 144 by 3 (144÷3 =48)
2) now you do the same thing multiply 22.5 and 48 (22.5 × 48= 1,080) and divide 1,080 by 18 (1,080 ÷ 18= 60)
3) multiply 27 times 60 (27 × 60= 1,620) now divide 1,620 by 22.5 (1,620 ÷ 22.5= 72)