X : the gas used by first car in 1 particular week
y : the gas used by second car in 1 particular week

Answer:
Moving the decimal 3 places to the right in a decimal number is the same as multiplying the number by 1000.
Answer:
40 minutes
Step-by-step explanation:
30x+45x=50
75x=50
x=.6667 hours or 40 minutes
check:
30 mph for 40 minutes=20 miles
45 mph for 40 minutes=30 miles
total=50 miles
Answer:
Step-by-step explanation:
i think its 500%
but im not sure
because 20 divided by 4 = 5
and 5.0 = 500%