Fill in ...
nine – five – two + three = five()
eight + three – five = six()
twelve – five – one + four + two = twelve()
seven + five – two + one = eleven()
ten – six() = four
eleven + one – six – two – two() = two
nine() + three – five + four = eleven
seven + two – five() + three = seven
ten – two – one + three() = ten