Addition and subtraction

  • Small tomato seedlings in pink pots.
    problem

    Highs and Lows

    Age
    11 to 14
    Challenge level
    1 out of 3

    What were the maximum and minimum temperatures recorded in my max/min thermometer?

  • 3388
    problem

    3388

    Age
    11 to 14
    Challenge level
    2 out of 3

    Using some or all of the operations of addition, subtraction, multiplication and division and using the digits 3, 3, 8 and 8 each once and only once make an expression equal to 24.

  • Aba
    problem

    Aba

    Age
    11 to 14
    Challenge level
    2 out of 3

    In the following sum the letters A, B, C, D, E and F stand for six distinct digits. Find all the ways of replacing the letters with digits so that the arithmetic is correct.

  • Eleven
    problem

    Eleven

    Age
    11 to 14
    Challenge level
    2 out of 3

    Replace each letter with a digit to make this addition correct.

  • Clocked
    problem

    Clocked

    Age
    11 to 14
    Challenge level
    2 out of 3

    Is it possible to rearrange the numbers 1,2......12 around a clock face in such a way that every two numbers in adjacent positions differ by any of 3, 4 or 5 hours?

  • Small tomato seedlings in pink pots.
    problem

    Rolling Along the Trail

    Age
    11 to 14
    Challenge level
    2 out of 3

    What could be the scores from five throws of this dice?

  • Football Sum
    problem

    Football Sum

    Age
    11 to 14
    Challenge level
    2 out of 3

    Find the values of the nine letters in the sum: FOOT + BALL = GAME

  • Pair Sums
    problem

    Pair Sums

    Age
    11 to 14
    Challenge level
    3 out of 3

    Five numbers added together in pairs produce: 0, 2, 4, 4, 6, 8, 9, 11, 13, 15 What are the five numbers?

  • Pairs
    problem

    Pairs

    Age
    11 to 14
    Challenge level
    3 out of 3

    Ann thought of 5 numbers and told Bob all the sums that could be made by adding the numbers in pairs. The list of sums is 6, 7, 8, 8, 9, 9, 10,10, 11, 12. Help Bob to find out which numbers Ann was thinking of.

  • Alphabetti Sudoku
    problem

    Alphabetti Sudoku

    Age
    11 to 16
    Challenge level
    1 out of 3

    This Sudoku requires you to do some working backwards before working forwards.