जब एक धाविका किसी दौड़ में 12 km दूरी दर्शाने वाले चिह्न को पार कर रही थी, तब उसे यह बताया गया कि उसने दौड़ का केवल 80% हिस्सा पूरा किया है । इस स्पर्धा में इस धाविका को कितने किलोमीटर दौड़ना था?
सही उत्तर: 16
माना दौड़ की कुल लंबाई X किलोमीटर है। प्रश्न के अनुसार, जब धाविका 12 km के चिह्न पर थी, तब उसने दौड़ का 80% पूरा कर लिया था। इसलिए, 80% of X = 12 (80 / 100) * X = 12 0.8 * X = 12 X = 12 / 0.8 = 15 km अतः इस स्पर्धा में धाविका को कुल 15 किलोमीटर दौड़ना था। विकल्प (ख) सही है।
In English (Question & Model Answer)
When a runner was crossing the 12 km mark, she was informed that she had completed only 80% of the race. How many kilometres was the runner supposed to run in this event?
Correct Option: 16
Let the total length of the race be X kilometres. According to the problem, when the runner was at the 12 km mark, she had completed 80% of the total race distance. We can set up the equation: 80% of X = 12 km. (80 / 100) * X = 12. 0.80 * X = 12. Solving for X: X = 12 / 0.80. X = 120 / 8. X = 15? Wait, let's calculate: 120 / 8 = 15 km? Wait, let's re-verify: 15 * 0.80 = 12. So total length of the race is 15 km. Wait, let's check the options: 14, 15, 16, 16.5. 15 is Option B (index 1). Let's double check: 80% of 15 = 0.8 * 15 = 12 km. Perfect! Thus, the runner was supposed to run 15 kilometres.