The school hockey team travelled 150 km to a tournament by bus. The bus drove at 90 km/h for most of the way, but was delayed by a storm, when its speed was only 30 km/h. If the trip took 3 hours, how far did the bus travel in the storm

90a + 30b = 150

a + b = 3

30a + 30b = 90

- (90a + 30b = 150)

-60a + 0 = - 60

a = 1

a + b = 3

1 + b = 3

b = 2

so they travelled 1 hour at 90k and 2 hours in the storm at 30k

The bus traveled 1 hour at 90 km/h and 2 hours in the storm at 30 km/h

Explanation:

From the example, let us recall the following statements

The school hockey team traveled 150 km to a tournament by bus.

The bus drove = 90 km/h for most of the way

The speed was only 30 km/h. when delayed by a storm

Now, lets find how far the bus travel in the storm

Given that

90x + 30y = 150

x + y = 3

30x + 30y = 90

- (90x + 30y = 150)

-60x + 0 = - 60

so,

x = 1

x + y = 3

1 + y = 3

y = 2

Therefore, they travelled 1 hour at 90km/h and 2 hours in the storm at 30km/h