Monica has been saving her spare change. So far, she has saved 40 coins for a total of $6.25. Some of the coins are quarters (25 cents), and the rest are dimes (10 cents).
How many of each coin does she have? Let the number of quarters = q and the
number of dimes = d.

good job you smart son of a gun you are smarter that einstein. 7

, 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