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7.4 Proportional Relationships and Percentages

I can find dimensions on scaled copies of a rectangle.
I remember how to compute percentages.

I can solve problems about ratios of fractions and decimals.

I can use a table with 2 rows and 2 columns to find an unknown value in a proportional relationship.
When there is a constant rate, I can identify the two quantities that are in a proportional relationship.

I can use the distributive property to rewrite an expression like $x+\frac12 x$ as $(1+\frac12)x$.
I understand that “half as much again” and “multiply by $\frac32$” mean the same thing.

I can use the distributive property to rewrite an equation like $x+0.5 x=1.5 x$.
I can write fractions as decimals.
I understand that “half as much again” and “multiply by 1.5” mean the same thing.

I can draw a tape diagram that represents a percent increase or decrease.
When I know a starting amount and the percent increase or decrease, I can find the new amount.

I can use a double number line diagram to help me solve percent increase and decrease problems.
I understand that if I know how much a quantity has grown, then the original amount represents 100%.
When I know the new amount and the percentage of increase or decrease, I can find the original amount.

I can solve percent increase and decrease problems by writing an equation to represent the situation and solving it.

I can find percentages of quantities like 12.5% and 0.4%.
I understand that to find 0.1% of an amount I have to multiply by 0.001.

I understand and can solve problems about sales tax and tip.

I understand and can solve problems about commission, interest, markups, and discounts.

I can find the percentage increase or decrease when I know the original amount and the new amount.

I can represent measurement error as a percentage of the correct measurement.
I understand that all measurements include some error.

I can solve problems that involve percent error.

I can find a range of possible values for a quantity if I know the maximum percent error and the correct value.

I can write and solve problems about real-world situations that involve percent increase and decrease.