Question

One fourth of all telephones at the office have built in speaker phones. One -half the phones with the built-in speaker phones have conference-call capability,how many of the phones in the office have both a speaker phone and a conference-call capability?

Answer 1

(1/8)x phones have both speaker phone and a conference call capability

Explanation:

Let the total phones be x

It is given that one forth of the phones have in built speaker = (1/4)x

It is also given that one half of the phone having built in speaker also have conference call capability = (1/2) of (1/4)x

= (1/8)x

Therefore, (1/4)x - (1/8)x

= (1/8)x

(1/8)x phones have both speaker phone and a conference call capability.

Answer 2

`(1)/(8)` of the phones in office has both a speaker phone and a conference-call capability

Explanation:

Since total number of phones in the office is not given, the answer will be "in that terms".

let it be x

So built in speaker phones is (1/4)x

Hence conference call phones would be (1/2)(1/4x) = (1/8)x

Hence "1/8th of the phones in office has both a speaker phone and a conference-call capability"