Simultaneous equations

There are 55 NRICH Mathematical resources connected to Simultaneous equations
Fruity Totals
problem
Favourite

Fruity totals

Age
7 to 16
Challenge level
filled star empty star empty star

In this interactivity each fruit has a hidden value. Can you deduce what each one is worth?

Multiplication arithmagons
problem
Favourite

Multiplication arithmagons

Age
14 to 16
Challenge level
filled star filled star empty star

Can you find the values at the vertices when you know the values on the edges of these multiplication arithmagons?

Leonardo's Problem
problem
Favourite

Leonardo's problem

Age
14 to 18
Challenge level
filled star filled star filled star
A, B & C own a half, a third and a sixth of a coin collection. Each grab some coins, return some, then share equally what they had put back, finishing with their own share. How rich are they?
Sweet Shop
problem
Favourite

Sweet shop

Age
11 to 14
Challenge level
filled star filled star empty star
Five children went into the sweet shop after school. There were choco bars, chews, mini eggs and lollypops, all costing under 50p. Suggest a way in which Nathan could spend all his money.
Quadratic Harmony
problem
Favourite

Quadratic harmony

Age
16 to 18
Challenge level
filled star empty star empty star
Find all positive integers a and b for which the two equations: x^2-ax+b = 0 and x^2-bx+a = 0 both have positive integer solutions.
Children at Large
problem
Favourite

Children at large

Age
11 to 14
Challenge level
filled star filled star empty star
There are four children in a family, two girls, Kate and Sally, and two boys, Tom and Ben. How old are the children?
Always Two
problem
Favourite

Always two

Age
14 to 18
Challenge level
filled star filled star empty star

Find all the triples of numbers a, b, c such that each one of them plus the product of the other two is always 2.

System Speak
problem
Favourite

System speak

Age
16 to 18
Challenge level
filled star empty star empty star
Five equations... five unknowns... can you solve the system?
Arithmagons
problem
Favourite

Arithmagons

Age
11 to 16
Challenge level
filled star empty star empty star

Can you find the values at the vertices when you know the values on the edges?

Surds
problem
Favourite

Surds

Age
14 to 16
Challenge level
filled star filled star empty star
Find the exact values of x, y and a satisfying the following system of equations: 1/(a+1) = a - 1 x + y = 2a x = ay