1. Luke can fill a small sandbox with sand in 4 minutes. However, his brother Drew, is taking sand out at the same time. If full, Drew can empty the sandbox in 6 minutes. How long will it take Luke to fill the sandbox if Drew is emptying it at the same time? 2. Two garden hoses are filling a kiddie pool together. Together they can fill the pool in 12 minutes. If used separately, one hose can fill the pool 10 minutes faster (not 10 times) than the other. How long does each hose take by itself to fill the pool?

f(x) = - 2/3x + 5; f(5/2)

substitute 5/2 in for x:

f(5/2) = -2/3(5/2) + 5

simplify the right side:

f(5/2) = -5/3 + 5

f(5/2) = 10/3

answer:

f(5/2) = 10/3

i hope this you!

, 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

probably the last option

step-by-step explanation: