Question

How to do the 15th question

Answer 1

Hey mate..
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Let , the part covered in 15 km/ h be x km

Then, the part covered in 18 km/h be ( 136 - x ) km/h

We know,

Time = Distance / Speed

A/Q,

$\frac{x}{15} + \frac{(136 - x)}{18} = 8 \\ \\ = > \frac{6x + 680 - 5x}{90} = 8 \\ \\ = > x + 680 = 8 \times 90 \\ \\ = > x = 720 - 680 \\ \\ = > x = 40$

Hence, the part covered at 15 km/h is 40 km

And, the part covered at 18 km/h is ( 136 - 40 ) km i.e. 96 km

Hope it helps !!