You have two coupons for a store. Coupon 1 is for $10 dollars off. Coupon 2 is for 15% off. Coupon 2 is for 15% off. You can only use one coupon. Decide when you should use coupon 1 and when you should coupon 2. Please explain the coupons apply to a minimum purchase of $20

Purchases greater than 66.67 dollars should use coupon 2, while purchases between 20 dollars and 66.67 should use coupon 1.

Step-by-step explanation:

Coupon 1 must be used as long as those 10 dollars represent more money than 15% of coupon 2.

For example, if the purchase is the minimum of $ 20, 10 dollars represents half of the purchase, therefore in this case it is better to use coupon 1.

In this case, coupon 2 would only be a discount of 3 dollars (20 * 0.15).

So when from what value would it be better to use coupon 2, it would have to be calculated when it is worth more than 10 dollars.

10 = x * 0.15

x = 10 / 0.15

x = 66.67

That is to say that from the purchases greater than 66.67 dollars, coupon 2 would have a discount equivalent to 10 dollars or more.

, and

for

step-by-step explanation:

we can analyze the pattern at which the terms increase. let us denote , , , so that we can call

note the following:

the pattern: to get the next term value, we just add the next term number (e.g. 1st, 2nd, to the previous term value (term values are the given numbers in the question, 1, 3, 6, 10, 15,

from , to get to , we add

from , to get to , we add

etc.

we need to form a recursive formula, a formula that has the next term as a function of the previous term. so a possible recursive formula can be

, and for