cal-coola: math brain game

"cal-coola": Simple brain challenge for all:
▷ 6 numbers, 4 operations... and 1 goal result
▷ Work out the goal result, or a close one
▷ The sooner you solve it, more points you get

Incredibly easy to play: 

▷ To calculate: Drag two tiles into +, -, ×, ÷

▷ To undo: Double-tap on the tile

▷ To finish: Drag tile to the target box