Joann is driving 549 miles to visit family in California. If she travels at an average
speed of 71 mph, estimate how many hours
her trip will take.
Estimate using compatible numbers. Enter
the number that belongs in the green box.
5[?]0 = 70 = 0

step-by-step explanation:

b and c

, 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