North Western Province 11 ශ්‍රේණිය ගණිතය 3 වාර පරීක්ෂණය 2024

Annual rates at 8% of an assessed value of Rs. 50 000

පිළිතුර: Rs. 4000

💡 ප්‍රශ්නයේ අදහස: වරිපනම යනු පළාත් පාලන ආයතනයට වසරකට ගෙවන බද්දකි. එය නිවසේ තක්සේරු වාර්ෂික වටිනාකමේ ප්‍රතිශතයක් නිසා රු. 50 000 න් 8% සොයන්න.

1. 18% භාගයක් ලෙස ලියන්න: 8/100.
2. 2තක්සේරු වටිනාකමෙන් ගුණ කරන්න: 8/100 × 50 000.
3. 350 000 ÷ 100 = 500, 500 × 8 = 4000. එබැවින් වරිපනම වසරකට රු. 4000.

✅ 50 000 න් 10% = 5000; 8% ඊට ටිකක් අඩු විය යුතු නිසා රු. 4000 ගැළපේ.

Isosceles triangle with an exterior angle 110°; find two angles

පිළිතුර: x = 70°, y = 40°

💡 ප්‍රශ්නයේ අදහස: C හි සරල රේඛාව භාවිතයෙන් එහි අභ්‍යන්තර කෝණය සොයන්න. සලකුණු කළ පාද දෙක සමාන නිසා ත්‍රිකෝණය සමද්විපාද වන අතර කෝණ දෙකක් සමාන වේ.

1. 1සරල රේඛාවක කෝණ එකතුව 180° නිසා ACB = 180° − 110° = 70°.
2. 2AB = BC (සලකුණු) නිසා ඒවාට සම්මුඛ කෝණ සමානයි: x (A හි) = ACB = 70°.
3. 3ත්‍රිකෝණයක කෝණ එකතුව 180°: y = 180° − 70° − 70° = 40°.

✅ බාහිර කෝණය 110° අභිමුඛ අභ්‍යන්තර කෝණ දෙකේ එකතුවට සමාන විය යුතුය: 70° + 40° = 110°. ගැළපේ.

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