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
It would take Samantha 40 minutes to run 5 miles!!!
Ok, so based on a survey - you know that out of 30 students, 11 said that their favourite subject is mathematics. :-)
This means that:
11/30 of these students think mathematics if their favourite subject.
Now, in order to answer your question, we are going to have to change the denominator of the fraction above to 1000. Whatever we do to the denominator of this fraction, we must do to the numerator of this fraction.
Example:
This means that rounded to the nearest ten, theoretically speaking, 370 students out of 1000 would say that mathematics is their favourite subject.
Answer:
Step-by-step explanation:
Answer:
22°
Step-by-step explanation:
Triangle KJL ≅ Triangle MJL (RHS)
[JL = JL(common), KL = LM(given), angle KLJ = angle MLJ(given)]
we come up to the conclusion that 4x + 6 = 3x + 10
x = 4
∴angle KJL = 4(4) + 6 = 22°