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## 'Sort Them Out (2)' printed from http://nrich.maths.org/

Thank you
to those who submitted solutions to this problem. There were plenty
of opportunities to practise calculations, and also to share
different strategies.

Courtenay and Max from Ickford Combined School
looked at the set of fifteen cards, as did Ms Bean's Math Whizzes
from Sylvan Park. They both noticed that the answers are numbers
between $21$ and $35$, and could be arranged in ascending or
descending order. Courtenay and Max explained how they sorted their
cards:

First we sorted them into the five time tables and the two times
table. Then we sorted them into ones that have a digit that is a
two or three and ones which have both. All cards were used.

Maya, Max, Josh, Amy, Dylan and Imi from Weeke
Primary solved the set of twenty cards:

All of the answers when put in order from smallest to largest go
from $110$ to $129$.

$10\times$ $5$th prime number = $110$

$37\times3 = 111$

$16\times 7 = 112$

$191 - 78 = 113$

$57\times2 = 114$

$23\times5 = 115$

$29\times4 = 116$

$13\times9 = 117$

twice $59$ = $118$

$17\times7 = 119$

$8\times15 = 120$

square of the $5$th prime number = $121$

double $61$ = $122$

$41\times3 = 123$

$4\times31 = 124$

$5$ squared x $5$ = $125$

$7\times18 = 126$

$216 - 89 =127$

$2$ squared x $2$ squared x $2$ squared x $2$ = $128$

$3\times43 = 129$

Well done, and thank you very much to all who
submitted solutions!