Exercise 5.1Question 1(i) 89Let given number be $a b$ i.e $10 a+b$ ∴ 89=$10 \times 8+9$(ii) $207=2 \times 100+0 \times 10+7$(iii) $\quad 369=100 \times 3+10 \times 6+9$Question 2Sol: Given number = 34 Number obtained by reverssing the digits = 43 sum = 34 + 43 =77 = 7 x 11i) when sum is divited by 11, quotient is 7 ii) Whew sum is divided by 7 , quotient is 11Question...
Wednesday, March 31, 2021
ML AGGARWAL CLASS 8 CHAPTER 4 Cubes and Cube Roots Excercise 4.1
Exercise 4.1Question 1(i) 648Sol: Expersing it in to prime factors $\begin{array}{r|l}2&648\\ \hline 2& 324 \\ \hline 2&162\\ \hline 3& 81\\ \hline 3& 9 \\ \hline 3&27\\ \hline 3& 9 \\ \hline 3&3\\ \hline &1\end{array}$648 = 2 x 2 x 2 x 3 x 3 x 3 x 3 = $2^{3} \times 3^{3} \times 3$Since 3 is left after grouping in triplets ∴ 648 is not perfect...
Sunday, March 21, 2021
ML AGGARWAL CLASS 8 CHAPTER 3 SQUARES AND ROOTS Exercise 3.1
Exercise 3.1Question 1(i) 729Sol :Prime fractorisation$\begin{array}{r|l}3&729\\ \hline 3& 243 \\ \hline 3&81\\ \hline 3& 27\\ \hline 3& 9 \\ \hline 3&3\\ \hline&1\end{array}$⇒729=3×3×3×3×3×3∴$729=27^{2}$because 729 can be expressed as product of pairs of equal prime factors. (ii) 5488Sol:$\begin{array}{r|l}2& 5488\\ \hline 2& 2744 \\ \hline 2&1372\\...
