Question

A bit travels at a speed of 8 km per hours for x hours and then for y hours at 7 km per hour. Total distance is 37 km with total time as 5 hours. Find x and y

Answer 1

Here, the speeds given are:

s1=8km/hr

s2=7km/hr

and time for each speed are:

t1=xhrs

t2=yhrs

As Distance= speed . time, then:

D1= s1 . t1= 8x

D2= s2 . t2=7y

Total distance= 37km

i.e. 8x +7y= 37km     

and total time= 5hrs

i.e. x+y= 5

so, use substitution method to solve this pair of equations

8x +7y =37 --------- 1

x +y = 5 ---------- 2

x=5-y -------------- 3

substitute equation 3 in equation 1

8(5-y) +7y = 37

40 – 8y +7y=37

40-y=37

-y=37-40

Y=3

Now, substitute y=3 in equation 2:

X + 3= 5

Answer 2

Answer:

yo

Step-by-step explanation: