3x6y4/-3x6y4 in simplest form

For this case we must simplify the following expression:

The signs "-" are canceled, then:

In this case, it is observed that we have a unitary fraction, which by definition is that which has the numerator equal to the denominator.

Example:

So:

1

Zane claims that 85% of his contacts have a phone number with a local area code. He has 225 contacts in his phone. He makes 5 samples by randomly choosing 20 contacts and records whether the number has a local area code or non-local area code in the table. Is Zane's claim supported by the data?

Step-by-step explanation: