Explanation: To solve this problem, we need to calculate the total distance Ria will cover when she travels from her town to Kolkata and then to Rani's town. The distance from Ria's town to Kolkata is 37 km, and the distance from Kolkata to Rani's town is 35 km 228 m.
First, we need to ensure that the units are consistent before performing the addition. The distance from Ria's town to Kolkata is already in kilometers, but the distance from Kolkata to Rani's town is given in kilometers and meters. We can convert the meters to kilometers to make the addition easier.
1 km = 1000 m
So, 228 m = 228 / 1000 km = 0.228 km
Now, the distance from Kolkata to Rani's town is 35 km + 0.228 km = 35.228 km.
Next, we add the two distances together:
37 km (Ria's town to Kolkata) + 35.228 km (Kolkata to Rani's town) = 72.228 km
To express this in the form of kilometers and meters, we convert the decimal part back to meters:
0.228 km = 0.228 * 1000 m = 228 m
Therefore, the total distance Ria will cover is 72 km 228 m.
This calculation shows that the correct answer is (D) 72 km 228 m. The other options are incorrect because they do not accurately represent the total distance Ria will cover based on the given distances. Option A (35 km 265 m) is incorrect because it is less than the distance from Ria's town to Kolkata alone. Option B (1 km 772 m) is incorrect because it is much smaller than the distance from Ria's town to Kolkata. Option C (71 km 772 m) is incorrect because it does not account for the exact distances given in the problem.
Understanding how to convert between kilometers and meters and how to add distances correctly is crucial for solving such problems. This skill is often tested in various competitive examinations, including UPSC, SSC, Bank PO, and State PSC, where candidates are expected to perform basic arithmetic operations and unit conversions accurately.