Math 2.A

Decide whether the following statement makes sense or does not make sense. Explain your reasoning. I have a box with a volume of 2 square feet.

The statement does not make sense because square feet is not a unit of volume.

Units

Units are words that describe what is being measured or counted.

Describe the three basic uses of percentages. Give a sample statement that uses percentages in each of the three ways.

A. Percentages can be used to express a fraction of something. For​ example, out of​ 15,000 employees,​ 3% lost their jobs.

Distinguish between absolute and relative difference

Absolute difference is the actual difference between the compared value and the reference value. Relative difference describes the size of the absolute difference in comparison to the reference value and can be expressed as a percentage.

What is the meaning of the key word​ "of"?

It implies multiplication.

What is the meaning of the key word​ "square," when used in the context of​ units?

It implies raising to the second power.

What is the meaning of the key word​ "cube," when used in the context of​ units?

It implies raising to the third power.

What is the meaning of the key word​ "per"?

It means for every and it says to divide.

Absolute Change

New-original

Relative Change

New-original/original Always percentages

What is the third way to use​ percentages?

Percentages can be used to compare two things. For​ example, the car costs​ 25% more but gets​ 10% more miles per gallon.

What is a second way to use​ percentages?

Percentages can be used to describe a change in something. For​ example, the cost of milk rose​ 5% within the past month

What are the basic metric units of​ length, mass,​ time, and​ volume? How are the metric prefixes​ used?

The basic metric units of​ length, mass,​ time, and volume are the meter​ (m) for​ length, the kilogram​ (kg) for​ mass, the second​ (s) for​ time, and the liter​ (L) for volume. These basic units can be combined with a prefix that indicates multiplication by a power of 10.

What is the meaning of a hyphen in​ units?

The hyphen means multiplication.