**Answer:**

45%

**Step-by-step explanation:**

The formula to work out the decrease is:

Percentage Decrease= actual decrease / original amount X 100%

**1) So firstly, we have to work out the decrease**, to do this we have to do is do $750-$412.50= $337.50

**2) We can now substitute this into our formula which will now be.** (We will also add the original amount, which is $750.00)

Percentage Decrease= 337.50 / 750.00 X 100% = 45

The percentage decrease is 45%

**Answer:**

work is pictured and shown

**Answer:**

The answer is at 8:00 o’clock.

**Step-by-step explanation:**

So the Martinez family started 30 min after the Smith’s family. Smith’s family started one hour before Carson’s family. So it means the Smith’s family started at 7:30 and Martinez family started 30 min later. It means at 8:00 o’clock.

**Answer:**

**Step-by-step explanation:**

**1**

**the initial level is below normal so it is represented by a negative number. the level continued to decrease in June and July so those changes are also represented by negative numbers. find the sum of these values to find what the new level was with respect to the normal level**

**2 **

**write the mixed numbers as improper fractions**

**3**

**get common denominator**

**4**

**add the numerators since all the numbers are negative and have a common denominator. write the improper fraction as a mixed number**