Work out 3¹/₄ − ⁵/₆. Give your answer as mixed number in its simplest form.

Adding the fraction parts:
5 and 7 both go into 35.
⁴/₅ = ²⁸/₃₅ (multiplying top and bottom by 7)
¹/₇ = ⁵/₃₅ (multiplying top and bottom by 5)
So ⁴/₅ + ¹/₇ = ²⁸/₃₅ + ⁵/₃₅ = ³³/₃₅

Adding the whole number parts:
2 + 3 = 5

So 2⁴/₅ + 3¹/₇ = 5³³/₃₅

Correct

2¹¹/₁₂ = ³⁵/₁₂ and 1³/₄ = ⁷/₄
12 and 4 both go into 12.
³⁵/₁₂ = ³⁵/₁₂ (denominator is already 12)
⁷/₄ = ²¹/₁₂ (multiplying top and bottom by 3)
So 2¹¹/₁₂ − 1³/₄ = ³⁵/₁₂ − ⁷/₄ = ³⁵/₁₂ − ²¹/₁₂ = ¹⁴/₁₂ = 1²/₁₂ = 1¹/₆