Worksheet generator

1.B — odd, 49KA-0002Parity of numbers (odd/even behavior)

• AI decided that adding odd numbers always keeps the total odd, and made an arithmetic slip as well.
• CI paired the numbers up and forgot that with seven numbers one is left over, so I expected an even total.
• DI added correctly but then labelled 49 as even because I had already decided the pairs would make it even.
• EI added only the first six numbers and stopped before including the thirteen.

2.C — 30KA-0006Number lines and betweenness

• AI counted the tick marks and gave the position number instead of reading the value on the scale.
• BI worked out that each gap is worth 10 but then counted only as far as the tick before the arrow.
• DI counted the tick marks rather than the gaps between them, so every gap came out one step too small.
• EI counted the gaps from the right-hand end instead of from zero.

3.D — ThursdayKA-0021Remainders and modular cycles

• AI found the remainder 2 but counted the two days starting from today rather than starting from tomorrow.
• BI divided 100 by 7 and used the quotient of 14, treating the leftover days as if there were none.
• CI remembered there was a remainder but used a remainder of 1 instead of working it out.
• EI counted 100 divided by 7 as 14 remainder 3 instead of remainder 2.

4.E — 60KA-0026Percentages and simple discounts

• AI worked out the size of the discount and gave that as the new price instead of subtracting it.
• BI treated a quarter off as half off and took the price down to 40.
• CI applied the 25% reduction twice, taking 80 down to 60 and then 60 down to 45.
• DI subtracted 25 euros rather than 25 percent, treating the percentage as an amount of money.

5.C — 9:36KA-0041Factors, multiples, LCM and GCD by listing

• AI found the greatest common divisor of 12 and 18 instead of the least common multiple.
• BI added the two intervals together rather than looking for a time that is a multiple of both.
• DI found a common multiple but not the least one, landing on a later coincidence.
• EI multiplied the two intervals together instead of finding their least common multiple.

6.C — 70KA-0055Place value and digit positions

• AI gave the last digit of the number instead of looking at the 7 at all.
• BI gave the digit itself rather than what it is worth in the position it sits in.
• DI counted the positions from the left, so I read the 7 as being in the hundreds place.
• EI gave the value of the largest digit instead of the value of the 7.

7.C — 210KA-0057Clever regrouping (pair to round numbers)

• AI paired the numbers from the outside in but left the 20 out of every pair, so I added only up to 19.
• BI estimated the total as a round number instead of working it out.
• DI used eleven pairs of 20 instead of ten pairs of 21.
• EI multiplied 20 by 21 and forgot that pairing counts every number twice.

8.D — 4320KA-0059Estimation and order of magnitude

• AI worked out the drips in an hour and stopped there.
• BI multiplied by the 24 hours but forgot the 60 minutes in each one.
• CI used 6 hours in a day, thinking of waking hours rather than a whole day.
• EI used 600 minutes in an hour rather than 60.

9.C — 5KA-0061Operation puzzles and cryptarithms

• AI solved for the triangle and gave that instead of the square.
• BI found the triangle is 4 and gave that number, without going on to the second equation.
• DI halved the 12 instead of dividing it by the three triangles.
• EI subtracted the wrong way round, taking 9 from a number instead of taking the triangle from 9.

10.B — 7KA-0064Fractions of a quantity

• AI divided 28 by 7 instead of taking a quarter of it.
• CI found three quarters of 16 by mistake, mixing up the class size.
• DI found how many did travel by bus and gave that instead of how many did not.
• EI subtracted the 4 quarters as if they were 4 students.

11.C — 2/5KA-0141Number lines and betweenness

• AI compared the bottom numbers and assumed a bigger denominator means a bigger fraction.
• BI saw that 4 lies between 3 and 2 and assumed one quarter therefore lies between the two fractions.
• DI checked that it is bigger than one third but never checked it against one half.
• EI compared the top numbers only and ignored what the bottoms do to the size.

12.C — 200 gKA-0151Ratio as parts of a whole

• AI worked out the part size correctly and then answered for the sugar instead of the flour.
• BI split the 320 grams into two halves instead of into eight equal parts.
• DI took three fifths of 320 rather than five eighths, using the ratio numbers as a fraction of each other.
• EI divided 320 by the 5 in the ratio and stopped, treating 5 as the number of parts.

13.B — 76.80 poundsKA-0153Percentages and simple discounts

• AI assumed a 20 percent rise and a 20 percent fall must cancel because the percentages match.
• CI applied only the fall and forgot the rise.
• DI got the size of the change right but the direction wrong.
• EI applied only the rise and forgot the fall.

14.C — 4KA-0161Remainders and modular cycles

• AI assumed the cycle ends on 1 at every exponent that is a multiple of 2.
• BI used a remainder of 1 rather than 2 when dividing 50 by 3.
• DI doubled my way to 2 cubed = 8 and used 8 minus 2.
• EI assumed a large power of 2 must eventually be divisible by 7.

15.A — 1KA-0169Remainders and modular cycles

• BI reduced 7 to 2 correctly but then used a remainder of 1 when dividing 100 by 4.
• CI read the cycle backwards and landed on the entry before the right one.
• DI used 100 divided by 4 giving 25 and read off the 25th entry as if the cycle had length 25.
• EI assumed a power that large must be divisible by 5.