Answer:
Amount of money Naviah spends each week is ranged from 18 to 30
( 18 ≤ m ≤ 30 )
Explanation:
Let Naviah buys gas each week = x gallons
As given,
Naviah buys at least 8 but no more than 12 gallons of gas each week.
⇒8 ≤ x ≤ 12
Now,
Let the price of gas each week = p
As given,
The price of gas ranged from 2.25 to 2.50 per gallon each week.
⇒2.25 ≤ y ≤ 2.50
Now,
Amount of money spend (m) = (Total gas buy)(Price of gas)
= xy
⇒ m = xy
Now,
we have
8 ≤ x ≤ 12 and 2.25 ≤ y ≤ 2.50
Multiply both the inequality , we get
8×2.25 ≤ x.y ≤ 12×2.50
⇒18 ≤ xy ≤ 30
⇒18 ≤ m ≤ 30
∴ we get
Amount of money Naviah spends each week is ranged from 18 to 30.