When asked how old she was, the teacher replied: My age in years is
not prime but odd and when reversed and added to my age you have a
Can you work out how many of each kind of pencil this student
Add up all 5 equations given below. What do you notice?
Solve the system and find the values of a, b, c , d and e.
b + c + d + e = 4
a + c + d + e = 5
a + b + d + e = 1
a + b + c + e = 2
a + b + c + d = 0
Very good solutions came in from Christopher Kassam, age 13,
Epsom; from Ian Green of Cooper's Coborn School; Lizzie and Sheli,
Ruoyi Sun, Sarah Rogers, Arti Patel from the NLCS Puzzle Club; Alex
Lam from St Peter's College, Adelaide; Beth Carroll, Sheila Luk,
Alicia Maultby and Rachel Walker from the Mount School, York; Alex
Filz from Ousedale School, Milton Keynes; Farhan Iskander, Foxford
School, Coventry; and Christopher Dorrington and Lorn Tao, Stamford
School. Well done all of you.
This is the solution from Lizzie and Sheli:
We realised that if you multiplied all the equations together and
simplified it you ended up with:
The solutions are therefore