AzizHusain

This doesn't make sense. How can x = something that has x.

If x = 1: 1 = (2+1)/1 ? NO & 1 = 2 + (1/1) ? NO.

Also, parentheses are very important! Is it (2+1)/x or 2+(1/x)?

Need parentheses for the n-2/3 part...could be (n-2)/3 or n - (2/3)...

Anyway, you can multiply both sides by 3 to get rid of the 1/3. From there, depending on where the parentheses go, you can solve the rest.

You can use the on-site calculator to solve for this.

First, find the conversion of cg to g. You know that centi means 100, so how many grams?

1.) Multiply both sides by 2.5 and add 62.5 to get x.

2.) Simply plug all the values into the formula for the z-score.

3.) The class has a total of 20+13+12+15 = ? students. What is 30% of ?. That is your answer. 

4.) 0.01 is the same as 1/100. 0.0062 is the same as 62/1000. Note that 4/99 is almost like 4/100. You should be able to figure out the order.

Add 8 to both sides and then divide that number by -15 to get m.

Distribute the 4.

Sorry, need to rework.

4. (there is always an invisible decimal after an integer).

You can use the on-site calculator to do this.

I assume 7/56, 3/14 and 9/11 are all supposed to be in parentheses. 

Do the parentheses first, then multiply and divide. Lastly, add.