A large truck, traveling 30 miles per hour, carries a letter from the central post office to the local post office. The letter is then loaded onto a local vehicle, which travels at an average speed of 10 miles per hour, until the letter reaches its destination. The large truck carried the letter for a minutes and the local vehicle carried the letter for b minutes. If the total distance that the letter travelled from the central post office to its destination was 24 miles, which of the following equations correctly relates a and b ?Choose 1 answer:(A) 6030a+6010b=24(B) 3060a+1060b=24(C) 30a+10b=24(D) 60⋅30a+60⋅10b=24
Q. A large truck, traveling 30 miles per hour, carries a letter from the central post office to the local post office. The letter is then loaded onto a local vehicle, which travels at an average speed of 10 miles per hour, until the letter reaches its destination. The large truck carried the letter for a minutes and the local vehicle carried the letter for b minutes. If the total distance that the letter travelled from the central post office to its destination was 24 miles, which of the following equations correctly relates a and b ?Choose 1 answer:(A) 6030a+6010b=24(B) 3060a+1060b=24(C) 30a+10b=24(D) 60⋅30a+60⋅10b=24
Convert to Hours: To find the correct equation, we need to convert the time in minutes to hours since the speeds are given in miles per hour. There are 60 minutes in an hour, so we divide the time in minutes by 60 to convert it to hours.
Large Truck Distance: For the large truck traveling at 30 miles per hour for a minutes, the distance covered is (30 miles/hour)×(60 minutes/houra minutes).
Local Vehicle Distance: For the local vehicle traveling at 10 miles per hour for b minutes, the distance covered is (10 miles/hour)×(60 minutes/hourb minutes).
Total Distance Equation: The total distance covered by both the large truck and the local vehicle is the sum of the distances they each covered, which equals 24 miles. So, we have the equation:egin{equation}(30 \text{ miles/hour}) \times (a / 60) + (10 \text{ miles/hour}) \times (b / 60) = 24 \text{ miles}.\end{equation}
Simplify Equation: Simplifying the equation, we get: (6030)a+(6010)b=24.
Further Simplify: Further simplifying, we divide both 30 and 10 by 60, which gives us:21a+61b=24.
Final Equation Match: The equation (21)a+(61)b=24 can be rewritten as: (6030)a+(6010)b=24, which matches answer choice (A).
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