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Jumps of ten and one

You learn to jump on or back in tens and ones without counting.

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How to work it out

  1. Check whether jumping by ten or one.
  2. Jumping by ten only changes the tens digit.
  3. Jumping by one changes the ones digit.
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100

52 + 10

  1. Jump on one ten.
  2. Only the tens digit changes: 5 becomes 6.
  3. So 52 + 10 = 62.
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100
More examples

29 + 1

  1. Jump on one.
  2. After 29 comes the next ten.
  3. So 29 + 1 = 30.
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100

60 − 1

  1. Jump back one.
  2. Before 60 comes 59.
  3. So 60 − 1 = 59.
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100