Calculating Meeting Time

This problem involves calculating the time it takes for two individuals, Rohit and Dinesh, to meet when travelling towards each other.

Given Information

• Distance between Rohit and Dinesh, d = 64 km
• Rohit's speed, v_R = 15 km/hr
• Dinesh's speed, v_D = 17 km/hr
• They are travelling towards each other.

Concept: Relative Speed

When two objects move towards each other, their speeds add up. This is called their relative speed. The formula for relative speed ($v_{rel}$) is:

$v_{rel} = v_R + v_D$

Step 1: Calculate Relative Speed

Add the speeds of Rohit and Dinesh:

$v_{rel} = 15 \text{ km/hr} + 17 \text{ km/hr} = 32 \text{ km/hr}$

Step 2: Calculate Time to Meet

The time ($t$) it takes for them to meet can be calculated using the formula:

$t = \frac{\text{Distance}}{\text{Relative Speed}} = \frac{d}{v_{rel}}$

Substitute the values:

$t = \frac{64 \text{ km}}{32 \text{ km/hr}}$

$t = 2 \text{ hours}$

Conclusion

Therefore, Rohit and Dinesh will meet in 2 hours.