Question

7.A person travels along a straight road first half of distance with a speed 36kmph and second half of distance with a speed 72km/h find the average speed of person.

Answer 1

To find:-

Average speed = ?

Formula:-

Average velocity or Average speed

$= \frac{n}{ \frac{1}{v1} + \frac{1}{v2} + ......... + \frac{1}{vn} }$

Solution:-

Given,

• 1st half of distance covered with a speed 36 km/h .
• And 2nd half of distance covered with a speed 72 km/h .

So,

• n = 2
• v1 = 36 km/h
• v2 = 72 km/h

Now, according to formula Average speed is

$\frac{2}{ \frac{1}{36} + \frac{1}{72} } \\ = \frac{2 \times 72}{2 + 1} \\ = \frac{2 \times 72}{3} \\ = 2 \times 24 \\ = 48 \frac{km}{h}$

Hope it helps to you.