It looks like you're using Internet Explorer 11 or older. This website works best with modern browsers such as the latest versions of Chrome, Firefox, Safari, and Edge. If you continue with this browser, you may see unexpected results.

# Math help from the Learning Centre

This guide provides useful resources for a wide variety of math topics. It is targeted at students enrolled in a math course or any other Centennial course that requires math knowledge and skills.

## Weight, Fluid Oral Volume and Temperature

• When converting body weight from lb to kg, round it to the nearest tenth.
• For fluid oral volume and temperature, round it to the nearest tenth as well.

Note: tenth stands for the first place after the decimal point. Refer to Decimals for detailed information.

Example:

30 lb = 13.6078 kg

To round 13.6078 to the nearest tenth, we look at the number on hundredth. If this number is in the range of 5 to 9, we round it up  by adding 1 to the tenth. Otherwise, we round it down to keep the tenth unchanged.

Since 0 is on hundredth, we round it down to 13.6:

30 lb = 13.6 kg ## Tablets/Capsules

• Round unscored tablets to the nearest whole number.
• Scored tablets maybe broken in half, so numbers of scored tablets should be rounded to the nearest half tablet.

Example 1: Unscored

Order: 600 mcg

In hand: 250 mcg/tablet

Dosage: 2.4 tablets

To round 2.4 to a whole number, we check the number on tenth. Since it is 4 on tenth, round down to 2 tablets.

Example 2: Scored

Order: 600 mcg

In hand: 250 mcg/tablet

Dosage: 2.4 tablets

Since 2.4 is between 2.25 and 2.50, 2.5 is the nearest half. Round it up to 2.5 tablets. ## Fluid Injectable Volume

• Round to the nearest hundredth if the volume is less than 1 mL;
• Round to the nearest tenth if the volume is greater than 1 ml.

Example 1:

0.345 mL

0.345 is less than 1, so it should be rounded to the nearest hundredth. On thousandth it is a 5, so round it up to 0.35 mL.

Example 2:

1.345 mL

1.345 is greater than 1, so it should be rounded to the nearest tenth. On hundredth it is a 4, so round it down to 1.3 mL.

## Intravenous

• Round to the nearest whole number for piggyback infusion, such as flow rate in gtt/min or mL/hr, and drop factor in gtt/mL as drops cannot be fractionated.
• Round to the nearest tenth for dose -based flow rate such as mg/mL.

Examples:

15.25 gtt/min should be rounded to 15 gtt/min;

249.71 mL/hr should be rounded to 250 mL/hr;*

20.612 gtt/mL should be rounded to 21 gtt/mL;

0.625 mg/mL should be rounded to 0.6 mg/mL.

Note: In the second example, we need to round 249.71 to a whole number. It is 9 on the place of ones, so when rounding it up we get 10, which means we will write 0 on the place of ones and add one to the place of tens. Therefore we finally got 250. 