ප්‍රශ්න 45ම, එක් එක් ප්‍රශ්නය පරීක්ෂා කරන දේ සමඟ. ඕනෑම එකක් ගෙදර සර් තුළ නොමිලේ උත්සාහ කර ඔබේ පිළිතුර පරීක්ෂා කරන්න.
First approximation of a square root using given squares
about 4.5
💡 ප්‍රශ්නයේ අදහස: වර්ගමූලයක පළමු සන්නිකර්ෂණය යනු දශමස්ථාන එකක් සහිත ආසන්නතම අගයයි. 20, 4.4 හා 4.5 හි වර්ග සමඟ සසඳන්න.
- 4.4² = 19.36; එය 20 ට වඩා 20 − 19.36 = 0.64 කින් අඩුය.
- 4.5² = 20.25; එය 20 ට වඩා 0.25 කින් පමණක් වැඩිය.
- 0.25 කුඩා පරතරය නිසා 20 වඩා ළඟ 4.5² ටයි.
- එබැවින් √20 ≈ 4.5.
✅ 4.5 × 4.5 = 20.25 යි; එය 20 ට ඉතා ළඟ නිසා 4.5 හොඳ ආසන්න අගයකි.
Working in English
A first approximation of a square root is the nearest value with one decimal place. Compare 20 with the squares of 4.4 and 4.5.
- 4.4² = 19.36, which is 20 − 19.36 = 0.64 below 20.
- 4.5² = 20.25, which is only 0.25 above 20.
- 0.25 is the smaller gap, so 20 is closer to 4.5².
- So √20 ≈ 4.5.
Whole task in man-days from work done on a fraction
60 man days
💡 ප්‍රශ්නයේ අදහස: වැඩ ප්‍රමාණය මිනිස් දින (මිනිසුන් × දින) වලින් මැනේ. කළ කොටසේ වැඩ සොයා මුළු වැඩයට ගුණ කරන්න.
- කාර්යයෙන් හතරෙන් එකක වැඩ = මිනිසුන් 5 × දින 3 = මිනිස් දින 15.
- මුළු කාර්යය හතරෙන් එක කොටස් 4 කි.
- මුළු කාර්යය = 4 × 15 = මිනිස් දින 60.
✅ 60 හි හතරෙන් එක 15 යි; එය මිනිසුන් 5 දෙනා දින 3 ක් වැඩ කිරීමට ගැළපේ.
Working in English
Work is measured in man-days (men × days). Find the work for the part done, then scale it up to the whole job.
- Work for a quarter of the task = 5 men × 3 days = 15 man-days.
- The whole task is 4 quarters.
- Whole task = 4 × 15 = 60 man-days.
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