Sung Lee invests $7,000 at age 18. He hopes the investment will be worth $14,000 when he turns 30. If the interest compounds continuously, approximately what rate of growth will he need to achieve his goal? Round to the nearest tenth of a percent.

According to the question,

Investment at the age of 30,

Investment at the age of 15,

Time,

          = 12 years

As we know,

For continuous compound interest:

→      

By substituting the values, we get

By taking "ln", we get

or,

            (%) p.a

Thus the above approach is right.

Learn more about rate of growth here:

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2.3%

Step-by-step explanation:

For continous compound interest

Where A is final value, P is initial investment, i is interest rate in decimal and t is period.

The time will be 30-18=12 years

Substituting $14000 for A, $7000 for P and 12 years for t

Introducing natural logarithms on both sides then 12i=ln 2

Making i the subject of formula then

i=ln 2 ÷12=0.05776226504666

The percentage rounded off will be 5.7% p.a

question: how many people can she serve?

answer: she can serve 16.66666667 people. so she can only give 16 people a complete serving.

question: does she have enough ice cream for her guests?

answer: no. explanation: she only has enough for 16 people to have a full serving. however, she can give a 17th person a partial serving.

b. 1.25 hr

step-by-step explanation:

if you have a constant speed of 60 mph, then you have a ratio between 60 mi. to 1 hr. dividing both sides by 60 we get the ratio

1 mi. to

then mult. both sides by 75 we get the ratio

75 mi. to

simplifying we get

75 mi. to

or 1.25 hr.