30. your parents' original purchase price was $1,550.00 plus 7.25% sales tax. they enter into an agreement where the interest (11.75% apr) is walved

for the first 12 months provided they make the required monthly payments; otherwise the interest is accrued from the date of purchase. they miss

the first payment due date. the late fee is $29.00. how much is the interest?

$16.27

$152.13

$195.33

$15.18

Step-by-step explanation:

To calculate credit card interests we need to use its balance, because if a person makes several purchases, then the balance will be different each day. But, in this problem, we assume that these parents only make one purchase, which is given.

We need to use the APR which is the Annual Percentage Rate, which is give by the credit card company. So, the normal procedure to calculate the interest that the parents will pay, we should calculate the Average Daily Balance and then divide it by number of days involved. But, again, in this problem, we have only one purchase all along, which means that the balance remains constant, during the complete 12 months period.

At the end, all these factors about the problem make it easier, because we only need to apply the APR to the final price of the purchase, due to the constant balance. In this sense, the final price is $1550 plus the sales tax (7.25%), that is:

As you can see, the final price is $1662.38, which was calculated considering the sales tax, that is, the price percentage extra.

Then, If we multiply this final price with the APR of the credit card:

Hence, the interest is $195.33

PD: When we operate percentages, we divide the number by 100, to have the decimal equivalence of the percentage.

the third picture

step-by-step explanation:

the answer   is 200

step-by-step explanation:

this is a problem about poisson probabilities.   i don't know if you've

already studied poisson distributions, or if you have a place to look

to read more about the subject.  

here's how you can see a poisson distribution coming.   when there are

a lot of events that may happen at any time (or any place), and when

you're counting how many of them happen at a particular time (or a

particular place), and each event is independent of the others, then

the result is a poisson distribution.   this is roughly true for the

chocolate chips; one chip being in a cookie has only a small effect on

the probability that another chip will be in the cookie.

once you know you have a poisson distribution, you know a lot.   there

is only one parameter to a poisson distribution, so if you know the

mean, you know everything.   the form of the distribution is

  probability of n chips = {[e^(-x)]*(x^n)} / (n! )