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Help me do pls I need help​

Help me do pls I need help​-example-1

1 Answer

6 votes

d = vt

a. 48 min = 0.8 h

slower = -

(x - y).0.8 = 6

x-y = 7.5 (i)

b. 36 min = 0.6 h

faster = +

(x+y).0.6 = 6

x+y = 10 (ii)

c. x - y = 7.5

y = x - 7.5

substitute into the second equation (ii)

x + (x-7.5) = 10

2x = 17.5

x = 8.75 km/h

time at usual speed x = 8.75:


\tt t =(6)/(8.75)=0.686 h = 41.16\:minute

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