Class-v-K.C.NAG-প্রশ্নমালা-5(৫)

Class-v-K.C.NAG-প্রশ্নমালা-5- এর সব অঙ্কগুলি সহজ ভাবে সমাধান করাহল।

ক। নিম্নের উত্তর গুলি কোনটি ঠিক কোনটি ভুল তাহা লিখঃ

(i). $8+6=6+8$

উত্তরঃ ঠিক ( যোগ বিনিময় নিয়ম মেনে চলে )

$(ii). 8+6-4=8-6+4$

সমাধানঃ $8+6-4=14-4=10$

এবং $8-6+4=2+4=6$

$\therefore 8+6-4 \neq 8-6+4$

উত্তরঃ ভুল

$(iii). 3 \times 9= 9 \times 3$

সমাধানঃ $3 \times 9= 27$

এবং $9 \times 3 = 27$

$\therefore 3 \times 9= 9 \times 3$

উত্তরঃ ঠিক ( গুন বিনিময় নিয়ম মেনে চলে )

$(iv). 3 \div 9= 9 \div 3$

সমাধানঃ

3 \div 9= \frac{1}{3}\\ 9 \div 3= 3 \\ 3 \div 9 \neq 9 \div 3

উত্তরঃ ভুল ( ভাগ বিনিময় নিয়ম মেনে চলে না )

$(v). 16 \div 4 \times 2 \div 4= 4 \times 2 \div 4$

সমাধানঃ

$16 \div 4 \times 2 \div 4 \\\\= 4\times 2 =8$

এবং $4 \times 2 \div 4=8 \div 4=2$

$\therefore 16 \div 4 \times 2 \div 4 \neq 4 \times 2 \div 4$

উত্তরঃ ভুল

(খ)। নিম্নের অঙ্কগুলিতে লুপ্ত চিহ্নগুলি বসাওঃ

$(i). 7-6*4+3=14*6=8$

সমাধানঃ $7-6+4+3=14-6= 8$

$(ii). 4 *2 \div 4 =8 * 4=2$

সমাধানঃ $4 \times 2 \div 4=8 \div 4= 2$

সরল করোঃ

$1. 6 \times 4 +8 \div2 -3 \times2$

সমাধানঃ

$6 \times 4 +8 \div2 -3 \times2\\\\= 24+4-6\\\\=28-6=22$

$2. 18\div6\times2-4\times2+10\div2$

সমাধানঃ

$18\div6\times2-4\times2+10\div2\\\\=3\times2-4\times2+5\\\\=6-8+5\\\\=11-8=3$

3. $27 \div 9 \div 3+8 \times 2 \div 4$

সমাধানঃ

$27 \div 9 \div 3+8 \times 2 \div 4\\\\=3 \div 3+ 8 \times \frac {1}{2}\\\\=1+4\\=5$

4. $224 \times 3 \div 4 \div 2 \times 25 \div 5$

সমাধানঃ

$224 \times 3 \div 4 \div 2 \times 25 \div 5\\\\=672 \div 4 \div 2 \times 5\\\\=168 \div 2 \times 5\\\\=84 \times 5\\\\=420$

5. $729 \div 9 \div 3 -15 \times 3 \div 9 -2 \times 7+8 \times 5$

সমাধানঃ

$729 \div 9 \div 3 -15 \times 3 \div 9 -2 \times 7+8 \times 5\\\\=81 \div 3 - 15 \times 3\div 9-14+40\\\\\=27-45 \div 9 +26\\\\=27-5+26\\\\=22+26=48$

6. $6 \times 5 \times 3 \times 4 \div 8 \div 5 \times 7 \times 3$

সমাধানঃ

$6 \times 5 \times 3 \times 4 \div 8 \div 5 \times 7 \times 3\\\\=360 \div 8 \div 5 \times 7 \times 3\\\\=45 \div 5 \times 7 \times 3\\\\=9 \times 7 \times 3\\\\=189$

7. $8+ (7-2+8)$

সমাধানঃ

$8+ (7-2+8)\\\\= 8 + (5+8)\\\\=8+13\\\\=21$

8. $12 - (6+3-7)$

সমাধানঃ

$12 - (6+3-7)\\\\=12-(9-7)\\\\=12-2\\\\=10$

9. $9 (7-3)-6(9+11)+9 \times 8(7-2)$

সমাধানঃ

$9 (7-3)-6(9+11)+9 \times 8(7-2)\\\\=9(4)-6(20)+9 \times 8(5)\\\\=36-120+9 \times 40\\\\=36-120+360\\\\=36+240\\\\=276$

10. $(6+7-4)-(17-14)+(8-21+13)-(4 \times 2-6)$

সমাধানঃ

$(6+7-4)-(17-14)+(8-21+13)-(4 \times 2-6)\\\\=(13-4)-(3)+0-(8-6)\\\\=9-3-2\\\\=9-5\\\\=4$

11. $(12 \div 4+2)(8 \times 2 \div 16 +1)$

সমাধানঃ

$(12 \div 4+2)(8 \times 2 \div 16 +1)\\\\= (3+2) (16 \div 16 +1)\\\\=(5)(1+1)\\\\=5 \times 2\\\\=10$

12. $(8+3-6)(2 +3)-(7-5)(7+3)$

সমাধানঃ

$(8+3-6)(2 +3)-(7-5)(7+3)\\\\=(11-6)(5)-(2)(10)\\\\=5 \times 5 - 2 \times 10\\\\=25-20 \\\\=5$

13. $250-(7+8-6-3)$

সমাধানঃ

$250-(7+8-6-3)\\\\= 250-(15-9)\\\\=250-6\\\\=244$

14. $18- \{9+(5 + \overline {8-6})\}$

সমাধানঃ

$18- \{9+(5 + \overline {8-6})\}\\\\=18-\{9+(5+2)\}\\\\=18-\{9+7\}\\\\=18-16\\\\=2$

15. $210- [8- \{7-(6+4-7)\}]$

সমাধানঃ

$210- [8- \{7-(6+4-7)\}]\\\\=210-[8-\{7-(10-7)\}]\\\\=210-[8-\{7-3\}]\\\\=210-[8-4]\\\\=210-4\\\\=206$

16. $9 \times 8-[5+ \{3-(5-3)\times 7 \}]$

সমাধানঃ

$9 \times 8-[5+ \{3-(5-3)\times 7 \}]\\\\=72-[5+\{3-2 \times 7\}]\\\\=72-[5+\{3-14\}]\\\\=72-[5+ \{-11\}]\\\\=72-[5-11]\\\\=72-[-6]\\\\=72+6\\\\=78$

17. $64+ [17-\{80-(21+19) \times 2\}]$

সমাধানঃ

$64+ [17-\{80-(21+19) \times 2\}]\\\\=64 + [17- \{80-40 \times 2\}]\\\\=64+ [17-\{80-80\}]\\\\=64 + [17]\\\\=81$

18. $72-[36-\{90+(70 \div 14)\}+64]\times 14$

সমাধানঃ

$72-[36-\{90+(70 \div 14)\}+64]\times 14\\\\=72-[36-\{90+5\}+64]\times 14\\\\=72-[36-95+64] \times 14\\\\=72-[100-95]\times14\\\\=72- 5 \times 14\\\\=72-70\\\\=2$

19. $\{18 \times 4 \div \overline {6 \times 2}-8 +\overline {54-47}\} \div (15\times 3\div 9)$

সমাধানঃ

$\{18 \times 4 \div \overline {6 \times 2}-8 +\overline {54-47}\} \div (15\times 3\div 9)\\\\=\{72 \div 12-8+7\} \div (45 \div 9)\\\\= \{6-8+7\} \div 5\\\\=\{ 13-8\} \div 5\\\\=5 \div 5\\\\=1$

20. $6 \times 15 + [8 \div 4 -(17- \overline {12+3})+(\overline{27-19}- \overline {34-29})]$

সমাধানঃ

$6 \times 15 + [8 \div 4 -(17- \overline {12+3})+(\overline{27-19}- \overline {34-29})]\\\\=90 +[2 -(17-15)+(8-5)]\\\\=90+[2-2+3]\\\\=90+3\\\\=93$

21. $[76-\{12 \times 11- \overline {4 \times 3+18} \div \overline{5 \times 3 \times2} \}+18 \times 5]$

সমাধানঃ

$[76-\{12 \times 11- \overline {4 \times 3+18} \div \overline{5 \times 3 \times2} \}+18 \times 5]\\\\=[76-\{132-\overline {12+18} \div 30 \} +90]\\\\= [76 - \{132-30\div 30\}+90]\\\\= [76-\{132-1\}+90]\\\\=[76-131+90]\\\\=[166-131]\\\\=35$

22. $81 \div \overline{19+8} +\{7 \times 8 -6 \times 9 - \overline {18-8\times 2 } +5 \}$

সমাধানঃ

$81 \div \overline{19+8} +\{7 \times 8 -6 \times 9 - \overline {18-8\times 2 } +5 \}\\\\=81 \div 27 + \{56 -54- \overline {18-16} +5\}\\\\= 3 +\{2-2+5\}\\\\=3+5\\\\=8$