Numbers Questions Answers

• 22. A number when divided by 44, gives 432 as quotient and 0 as remainder. What will be the remainder when dividing the same number by 31

  1. 5
  2. 3
  3. 4
  4. 6

  Answer :

  Option A

  Explanation:

  P ÷ 44 = 432
  
  => P = 432 * 44 = 19008
  
  P / 31 = 19008 / 31 = 613, remainder = 5

• 23. Find the unit digit in \begin{aligned}
  (544)^{102} + (544)^{103}
  \end{aligned}

  1. 2
  2. 4
  3. 0
  4. 1

  Answer :

  Option C

  Explanation:

  Required digit is = \begin{aligned}
  (4)^{102} + (4)^{103} \end{aligned}
  as \begin{aligned} (4)^2 \end{aligned} gives unit digit 6 so \begin{aligned} (4)^{102} \end{aligned} unit digit is 6 and \begin{aligned} (4)^{103} \end{aligned} unit digit is, unit digit of \begin{aligned} 6 \times 4 \end{aligned}= 4, so answer will be unit digit of 6 + 4 = 0
  

• 24. 1939392 * 625

  1. 1212120010
  2. 1212120000
  3. 1212120011
  4. 1212121010

  Answer :

  Option B

  Explanation:

  Trick: when multiplying with \begin{aligned} 5^n
  \end{aligned} then put n zeros to the right of multiplicand and divide the number with \begin{aligned} 2^n
  \end{aligned}
  So using this we can solve this question in much less
  time.
  \begin{aligned} 1939392 \times 5^4 = \frac {19393920000}{16} = 1212120000
  \end{aligned}

• 25. For the integer n, if n*n*n is odd, then what is true

  1. n is odd and n*n is even
  2. n*n is odd
  3. n is even
  4. n*n is odd

  Answer :

  Option A