Question

Juan roller skated for 2 hours 40 minutes with a constant speed of 18 m/h and then for another 1 hour 50 minutes with a constant speed of 24 m/h. What distance did he go?

Answer 1

Answer: 136 m

Step-by-step explanation:

For first interval,

Time = 2 hours 40 minutes  = $2+\dfrac{40}{60}\text{ hours}\ [\text{1 hour = 60 minutes}]$

$=2+\dfrac{2}{3}=\dfrac{8}{3}\ \text{hours}$

Speed = 18 m/h

Distance = $\dfrac{8}{3}\times18=48\ m$[Formula : Distance=Speed x time]

For second interval,

Time = 1 hour 50 minutes  = $1+\dfrac{50}{60}\text{ hours}\ [\text{1 hour = 60 minutes}]$

$=1+\dfrac{5}{6}=\dfrac{11}{3}\ \text{hours}$

Speed = 24 m/h

Distance = $\dfrac{11}{3}\times24=88\ m$

Total distance = 48 m +88 m = 136 m

Hence, he went 136 m.