Number patterns - Wiki

  • #numberpatterns
    • Jane is standing in a queue. She is the `4^(th)` person from the front and the `17^(th)` person from the back. How many people are there in the queue? Ans: _BLANK_
      • #numberpatterns

        Jane is 17th person from the back, that means there are 16 people behind her in queue

        No. of people in the queue

        4 + 16 = 20

    • The table below shows the method used to compute the sum of different sets of consecutive numbers. a) Find the sum of number from 1 to 40. b_ The multiples of 7 and the multiples of 9 were excluded from the set of numbers 1 to 40. Find the sum of the remaining numbers in this set. Ans: a) _BLANK_ [1] Ans: b) _BLANK_ [3]
      • #numberpatterns

        (part a):

        Sum of number from 1 to 40

        (40 `xx` 41) `-:` 2

        1640 `-:` 2

        820

        (part b):

        Multiples of 7 (up to 40)

        7,14,21,28,35

        Multiple of 9 (up to 40)

        9,18,27,36

        Total of the multiples

        7 + 14 + 21+ 28 + 36 + 9 + 18 + 27 + 36 = 195

        Sum of remaining numbers

        820 - 195

        = 625