10⅕-7⅖. We can see that in the fractions we are subtracting a larger fraction (⅖) from a smaller one (⅕). The way round this is to “borrow” some fifths from the whole number. If we borrow 5 fifths it makes a whole, so we can write 10⅕ as 9+⁵⁄₅+⅕, which is equal to 9+⁶⁄₅. This time we are subtracting a smaller fraction (⅖) from a larger one (⁶⁄₅), leaving ⅘. Now we subtract 7 from 9 leaving 2 and put in the fraction ⅘, giving us 2⅘ as the answer.