Answer:
Step-by-step explanation:
Declaration
Let Heather's number of messages = x
Let Eric's number of messages = x + 9
Let Chang's number of messages = 3(x +9)
Equation
x + x + 9 + 3(x + 9) = 116
Solution
x + x + 9 + 3(x + 9) = 116 Remove the brackets
x + x + 9 + 3x + 27 = 116 Combine like terms
x + x + 3x + 9 + 27 = 116
5x + 36 = 116 Subtract 36 from both sides
5x + 36 - 36 = 116 - 36 Combine
5x = 80 Divide both sides by 5
5x/5 = 80/5
x = 16
Answer
Heather = 16
Eric = 16 + 9 = 25
Chang = 3*25 = 75
We need to convert the mileage from mi/gal units into to km/L units using the conversion factors.
(31.0 mi/gal) x (1 km / 0.6214 mi) x (1 gal / 3.78 L) = 13.20 km/L
Next, we divide the distance by the mileage.
(142 km) / (13.20 km/L) = 10.79 L
<span>Therefore, you need 10.79 liters of gasoline.</span>
Answer:
7.02 x 10^1
Step-by-step explanation:
