Answer:
6.4 minutes, or 6 minutes and 24 seconds
Step-by-step explanation:
She is running 4 laps, so she is running 1600 meters total. If she runs 250 meters per minute, divide 1600 by 250 to determine how many minutes it will take...
1600/250 = 6.4
Which is 6 minutes + 0.4 minutes
*there are 60 seconds in a minute, so the 0.4 represents 40% of another minute. Multiply 60 by 0.4 to see how many seconds this is...
(0.4)60 = 24 seconds,
So she ran the laps in 6 minutes and 24 seconds
Answer:
131
Step-by-step explanation:
Using proportion,
If Out of 550 calculators = 6 are defective,
Then out of 12000 calculators = ? are defective

= 21.8 * 6
= 130.8 ≈ 131
∴ Approximately 131 calculators are defective
Answer:
It'll take 38.3 years to obtain the desired return of $25,000.
Step-by-step explanation:
In order to solve a continuosly coumponded interest question we need to apply the correct formula that is given bellow:
M = C*e^(r*t)
Where M is the final value, C is the initial value, r is the interest rate and t is the time at which the money was applied. Since he wants an return of $25,000 his final value must be the sum of the initial value with the desired return. So we have:
(25000 + 8000) = 8000*e^(0.037*t)
33000 = 8000*e^(0.037*t)
e^(0.037*t) = 33000/8000
e^(0.037*t) = 4.125
ln[e^(0.037*t)] = ln(4.125)
t = ln(4.125)/(0.037)
t = 1.4171/0.037 = 38.2991
t = 38.3 years