Jamilla is moving to a new city. she researches the rates charged by the local unity company for water. she finds the listing rate explanations below. she expects that her family may use up to 1000 cubic feet of water each month.

-$12.70 monthly service fee
-first 300 cubic feet of water used: $3.90 per 100 cubic feet, or fraction thereof
-after the first 300 cubic feet: $5.20 per 100 cubic feet, or fraction thereof

a.) sketch a graph of the cot of jamilla's possible water usage in one month. consider what the cost would be for partial units as 220 or 675 cubic ft of water

We put cubic feet of water used on the x-axis and the cost on the y-axis.
The graph will start at (0 , 12.7) because this is the fees before using any water.
The slope of the graph from 0 < x < 300 will be $0.039/cubic ft, and this interval will start at (0 , 12.7) and end at (300 , 24.4).
The slope of the graph for x > 300 will be $0.052/cubic ft, and this interval will start at (300 , 24.4) and continue to x value infinity.

220 units lies within the interval 0 < x < 300 so we use the first slope.
y = 0.039(220) + 12.57
= $21.15
We break 675 cubic feet into two parts, 300 + 375 cubic feet as they will be charged differently.
The cost of the first 300 cubic feet = $24.40
The cost of the remaining 375 cubic feet = 0.052 x 375 = $19.50
Total cost of 675 cubic feet = $43.90

5/8 beds for each square yard

, and

for

step-by-step explanation:

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

1 the 1st term, 3 the 2nd term, 6 the 3rd term,etc.

note the following:

from the 1st term (1) to the 2nd term (3), we go up by 2,from the 2nd term (3) to the 3rd term (6), we go up by 3from the 3rd term (6) to the 4th term (10), we go up by 4, andfrom the 4th term (10) to the 5th term (15), we go up by 5.

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