Answer:
see explanation
Step-by-step explanation:
In terms of prime factors
84 = 2 × 2 × 3 × 7 = 2² × 3 × 7
210 = 2 × 3 × 5 × 7
Thus
[tex]\frac{84}{210}[/tex]
= [tex]\frac{2^2(3)(7)}{2(3)(5)(7)}[/tex]
Cancelling 2, 3 and 7 on the numerator and denominator, leaves
[tex]\frac{2}{5}[/tex]
