Exercise 5.1- Playing with Numbers RD Sharma Solutions | Mathematics (Maths) Class 8 PDF Download

 Page 1


Q u e s t i o n : 1
Without performing actual addition and division write the quotient when the sum of 69 and 96 is divided by
i
11
ii
15
S o l u t i o n :
i
Clearly, 69 and 96 are two numbers such that one can be obtained be reversing the digits of the other. Therefore, when the sum of 69 and 96 is divided by 11, we get 15 sumofthedigits
as quotient.
ii
Clearly, 69 and 96 are two numbers such that one can be obtained be reversing the digits of the other. Therefore, when the sum of 69 and 96 is divided by 15 sumofthedigits
, we obtain 11 as quotient.
Q u e s t i o n : 2
Without performing actual computations, find the quotient when 94 - 49 is divided by
i
9
ii
5
S o l u t i o n :
(i) We know that when ab -ba  is divided by 9, the quotient is a -b. Therefore, when (94 -49) is divided by 9, the quotient is (9 -4 = 5). (ii) We know that when ab -ba is divided by (a -b), the
Q u e s t i o n : 3
If sum of the number 985 and two other numbers obtained by arranging the digits of 985 in cyclic order is divided by 111, 22 and 37 respectively. Find the quotient in each case.
S o l u t i o n :
The sum of 985 +859 +598 when divided by: i 111Quotient = 9 +8 +5 = 22 ii 22, i. e, 9 +8 +5 Quotient = 111 iii 37 = 
111
3
Quotient = 3 9 +8 +5 = 66
Q u e s t i o n : 4
Find the quotient when the difference of 985 and 958 is divided by 9.
S o l u t i o n :
If abc -acb is divided by 9, the quotient is (b -c). ? If (985 -958) is divided by 9, quotient = (8 -5) = 3
    
               
                                        
         
        
                                    
        
           
                                   
    
               
                                    
 
               
                                    
 
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