Joaquin bought a dvd for $21. he gave the cashier$40. how many different combos of $1 $5 $10 can the cashier give him for change

I BE LIKE IDK!

Step-by-step explanation:

You know somebody deleted my answer but that aint stoppin' me from just saying random things ok peeps, ok cool

answer is : muchas/tipicas

have a nice day!

~recklesschicken

, 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