Find 2 numbers the quotient between then estimate 284 divided by 5

Find the domain of the following expression: 1/(√x)-2

Recall that the owner of a local health food store recently started a new ad campaign to attract more business and wants to know if average daily sales have increased. historically average daily sales were approximately $2,700. the upper bound of the 95% range of likely sample means for this one-sided test is approximately $2,843.44. if the owner took a random sample of forty-five days and found that daily average sales were now $2,984, what can she conclude at the 95% confidence level?

The difference of three and the reciprocal of a number is equal to the quotient of 20 and the number. find the number.