A box contains 25 mangoes out of which 5 are spoilt. If five mangoes are chosen at random, find the probability that A number is selected at random from first fifty natural numbers. What is the chance that it is a multiple of either 7 or 9? Choose the correct choice.
A) 17/25	B) 1/25	C) 6/25	D) 7/25	E) 9/25
The probability that the number is a multiple of 7 is 7/50. (Since 7*7= 
<gadget id="calculator">7*7</gadget>
<output>49</output>
49).   Similarly the probability that the number is a multiple of 9 is 5/50. {Since   9*5= 
<gadget id="calculator">  9*5</gadget>
<output>45</output>
45).   Neither 7 nor 9 has common multiple from 1 to 50. Hence these events are mutually exclusive events. Therefore chance that the selected number is a multiple of 7 or 9 is (7+5)/50= 6/25.   ANSWER:6/25
<result>C</result>
A box contains 25 mangoes out of which 5 are spoilt. If five mangoes are chosen at random, find the probability that A number is selected at random from first fifty natural numbers. What is the chance that it is a multiple of either 7 or 9?