Decimals are a number and a dot and more numbers
The equation you can use is x + 3x = 428 with x as the number of cheeseburgers and 3x the number of hamburgers
you solve for x and get 4x= 428 and x=107
so 321 hamburgers were sold that day.
Given that the two swimmers competed and Ursula's speed is 60 m/min while Andre's speed is 48 m/min. The distance that the Ursula will catch up with Andre will be:
distance=(relative speed)×(time)
relative speed=60-48=12 m/min
the two swimmers met at a distance of:
12×1
=12 meters
Use the zeroes to figure this out... x=-18, y=9
