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Exam
Numerical Ability
Number System
A certain number when successively divided by 5 and 7 leaves the remainders 3 and 4 respectively. What is the remainder, if the same number is divided by 35?
(a)21
(b)23
(c)24
(d)29
Read Solution (Total 4)
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- ANSWER==> b.23
let's find the number
Number= X(say)
X/5= y+ 3 remainder
Y/7= 1 + 4 remainder
so Y=7*1 +4 =11
X = 11*5 + 3 = 58
Now 58/35 gives remainder = 23 - 10 years agoHelpfull: Yes(6) No(12)
- Let X is the number
Given Points are
X=5Y+3 . . . . . (1)
Y=7Z+4 . . . . . (2)
Putting Y value in 1st equation we will get
X=35z+23
Hence when X is divided by 35 it will leave 23 as remainder. - 7 years agoHelpfull: Yes(5) No(1)
- Overall we can solve this using remainder understanding. Here we use successive division for this.
In this case as number was successively divided by 5 and 7 leaving remainders 3 & 5 respectively.
If a number leaves remainder 3 when divided by 5, then it can be expressed as (5p+3). Now 'p' is the quotient after first division.
When ‘p' is divided by 7, it leaves remainder 4.
So, ‘p' can be expressed as (7q+4)
Thus the number should be: [5 x (7q+4) + 3] = (35k + 23)
Now when the number is divided by 35, the remainder will be:
R[(35k+23)/35]
= R[(35k)/35] + R[23/35]
= 0 + 23
= 23 Which is the required answer! Thanks. Option B. - 5 years agoHelpfull: Yes(0) No(0)
- b) refernce rs agarawal chapter 1 - numbers
- 4 years agoHelpfull: Yes(0) No(0)
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