Given that C⊂D means C is present entirely inside D. Which is shown below.
P(DC)=P(D)P(C∩D)=P(D)P(C)As C∩D means common part of events C and D which is equal to C.
0≤P(D)≤1∴P(D)P(C)≥P(C)Note: Here we are dividing with P(D) which is ≤1 and ≥0, as we know on dividing with a number n in the range 0≤n≤1 we get always more than or equal to the original number.