A man travels from Town A to Town B at an average speed of 4km/h and from Town B to Town A at an average speed of 6km/h. If he takes 45 minutes to complete the entire journey, find his total distance travelled.
Q. A man travels from Town A to Town B at an average speed of 4km/h and from Town B to Town A at an average speed of 6km/h. If he takes 45 minutes to complete the entire journey, find his total distance travelled.
Convert to Hours: First, let's convert the time taken for the entire journey from minutes to hours, since the speeds are given in kilometers per hour (km/h).45 minutes is equal to 6045 hours.6045=43 hours.
Distance Calculation: Now, let's denote the distance from Town A to Town B as D kilometers. The man travels this distance twice, once from A to B and once from B to A. The total time taken for the journey is the sum of the time taken to travel from A to B and the time taken to travel from B to A.
Total Time Equation: The time taken to travel from A to B at 4km/h is 4D hours, and the time taken to travel from B to A at 6km/h is 6D hours.The total time for the journey is therefore 4D+6D hours.
Solve for Distance: We know the total time for the journey is 43 hours, so we can set up the equation:4D+6D=43To solve for D, we need to find a common denominator for the fractions on the left side of the equation.
Calculate Total Distance: The least common multiple of 4 and 6 is 12. We multiply each term by 12 to clear the denominators:12×(D/4)+12×(D/6)=12×(3/4)This simplifies to:3D+2D=9
Calculate Total Distance: The least common multiple of 4 and 6 is 12. We multiply each term by 12 to clear the denominators:12×(D/4)+12×(D/6)=12×(3/4)This simplifies to:3D+2D=9 Combining like terms, we get:5D=9Now, we solve for D by dividing both sides of the equation by 5:D=9/560 kilometers
Calculate Total Distance: The least common multiple of 4 and 6 is 12. We multiply each term by 12 to clear the denominators:12×(4D)+12×(6D)=12×(43)This simplifies to:3D+2D=9Combining like terms, we get:5D=9Now, we solve for D by dividing both sides of the equation by 5:D=59D=1.8 kilometersSince the man travels the distance D from Town A to Town B and then the same distance back from Town B to Town A, the total distance traveled is 2D.2D=2×1.8=3.6 kilometers
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