Foundation June 2017 Paper 1 Q19

19. Amy needs 14 identical pieces of ribbon to gift wrap some presents.
Amy has two rolls of ribbon that are the same length.
She cuts 10 pieces from the first roll of ribbon and has none left over.
She cuts the remaining pieces from the second roll of ribbon and has 9 metres left over.

If each piece of ribbon is \(r\) metres long, work out the value of \(r\). [3]