calculets: Math game puzzle

calculets! Very simple math game for initial arithmetic.
Practice math operations:
Addition, subtraction, multiplication and division.
How to play calculets?
START: Upon starting, after choosing one of the three available levels, you will find:
- 6 numbers inside bubbles, in the central square
- one more number (the "target number"), at the bottom right of the screen
WIN: To win you have to reach the "target number",
combining the numbers inside the bubbles with the available mathematical operations:
+ addition
- subtraction
× multiplication
÷ division
HOW THE BUBBLES COMBINE: Drag two bubbles, one after the other, to the box with the + symbol, and they will automatically merge into a new bubble with the number corresponding to their sum.
And the same for subtracting, multiplying or dividing:
drag the bubbles to the boxes marked -, × & ÷
.
sssshhh ... a tip:
To undo an operation: double-tap a pink bubble to re-divide it into the two original bubbles.

Play calculets!