Reasoning with Ratios
What does a ratio compare?
Two (or more) quantities
Which is farther from zero:
-7 or 5?
-7
The distance around a circle is called the...
circumference
In a dataset, what is the "middle" value called?
The median
What does an equation HAVE to have?
An equals sign
A recipe uses 2 cups of water for every 1 cup of rice. If the amount of rice doubles, what happens to the water?
The water also doubles.
True or false:
A negative plus a negative is always negative
True
If the radis doubles, what happens to the circumference?
It also doubles
Which graph is best for showing parts of a whole?
A circle graph
What does a variable represent
An unkown or changing value
Which of these is a proportional relationship:
- Every group of ten pencils costs $3
- Each day of the week you run a different number of miles
- A tree grows 2 inches one year, then 3 inches the next year
Every group of ten pencils costs $3
Why is -3 x -4 positive?
Because multiplying two negatives always makes a positive number
A student says the area of a circle is 50 meters. What is missing from the answer?
The student needs to say "50 square meters"
A data set has one very large outlier. Which will this affect the most, the mean, median, range, or mode?
Mean
Which expression represents "5 more than an unknown number."
x + 5
When you graph a proportional relationship on the coordinate plane, does it pass through the origin?
Yes. Because when one value is zero, the other is also zero.
Which situation could be represented by a negative integer?
- Earning money
- Gaining followers
- Temperatures below zero
Temperatures below zero
A student covers a floor with tiles and says they found the perimeter.
What mistake did they make?
They found area, not perimeter
Two classes took the same quiz. The mean score for both classes was 82. Does this mean both classes had all the exact same scores?
No, two different datasets can have the same mean
A student solves x + 4 = 10 by adding 4 to each side. What did they do wrong?
They should subtract 4
What is the name for numbers that can NOT be written as a fraction?
Irrational numbers
True or false: The integers are only the positive and negative whole numbers.
If it's false, why?
False, because zero is neither positive nor negative
If you double the lengths of the sides of a rectangel, what happens to the area?
It becomes 4 times larger
"If two graphs have the same range, the data must be the same."
Why is this incorrect?
Why do we have to do the same thing on both sides of an equation?
To keep the equation balanced