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Unlocking the Case

Age 7 to 11
Challenge Level Yellow star
  • Problem
  • Getting Started
  • Student Solutions
  • Teachers' Resources

Well it has been very interesting looking at over $80$ solutions that came in with over $20$ different ideas as to what could unlock the case. Here are the codes and the names of those who suggested them.

$1916$ because T is the $19$th letter from Lance

$1652$ because T$16$ must be a sorting code from Rumanpreet

$916$ because T means Total from Tommy

$816$ because T is at the $8$ on a phone from Danny, Tubby, Daniel, Connor, Josh, Evie, Maddy and Portia

$773$ because T$16$ means $17$ so it has to add to that from Ediz

$716$ because T is $7$th from the end of the alphabet from Class 4/5B, Koya, Drew and Jje.

$672$ from Paneet, Any and Soneeshun for no particular reason

$376$ Yriel suggested this by using formula

$320$ because T is the $20$th letter and $20$x$16$ from Mattias, Georgia, Evie, Callum and Angus

$316$ because T means $10$ and they have to add to ten from Molescroft Primary School

$256$ because T means Times from William, Harry

$216$ because T is the $20$th and there's only $3$ spaces from Ben, Rowan,Kavo, Evie, Maddy, Portia, Nika and Ryan, Jake

$207$ because T is the $20$th and $1+6=7$ from Luke M, Danyal and Zak

$160$ because T means Tens from 'Primary 5', Asher, Sarah, Saloa, Michael, Hiruthika, Kieran and Ethan, another Ethan

$136$ this was the most popular answer with pupils considering that the T meant triangular number. Those who suggested this were Molly, Harry, Josie, 'Best Friends', Tallulah, 'ICT(2-)' 'GROUP1', Miles, Anna, George, Ari and Shail, Surichi, James

$116$ because T means Tens and you loose the Zero from Alya, Tom and Isaac. Isaiah also went for this number pointing out that T is $1$ in Scrabble, also because T means Twice, two $1$'s and then put the $6$ from Noor

T$48$ because T means $3$ times from Zamira

$048$ because T means $3$ times from Miles and Kieran

$20$P becuase T is the $20$th and the $16$th letter is P from Charlotte and Laura

 

Now look at what Sophia wrote;

 

You go to the Collins Cobuild Student Dictionary and find the T section you, find the page number, $713$ add on the $16$, use the initials of the dictionaries names number $3, 3, 19, 4,$ add them all together and you get $761$

 

A special mention to all those from Salcombe Prep School who sent in separate solutions, namely, Tallulah, Callim, Alya, Danyal. Surichi, Zamira, Anna, George, Ari, Nika, Charlie, Louis and Ediz.

 

Well done all of you, there are some really good and creative ideas to this challenge. Keep up your good mathematics work!

 

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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