Aidan has four cards with +, –, ×, ÷ printed on them.
He inserts them between the five
numbers 5, 4, 3, 2 and 1 to form the
expression 5 + 4 × 3 – 2 ÷ 1, which
has the value 15.
Emma says:
“Aidan put the operation cards in the order +, ×, –, ÷.
If I place the operation cards in a different order between the
numbers 5, 4, 3, 2, 1, I can make the value equal to 19.”
In what order did Emma place the four operations?