Direct Variation and Percentages

Front

What is direct variation?

Back

Direct variation is a relationship between two variables where one variable is a constant multiple of the other. If y varies directly with x, then y = kx, where k is a non-zero constant.

Front

How do you calculate the percentage increase?

Back

Percentage increase = ((New Value - Original Value) / Original Value) * 100.

Front

If Israel's savings account increased from $750 to $795, what is the percentage increase?

Back

6%.

Front

What is the formula for finding the time taken if the number of words typed varies directly with time?

Back

Time = (Number of words / Rate of words per minute).

Front

If Richard types 315 words in 9 minutes, how long will it take him to type 1,225 words?

Back

35 minutes.

Front

What is the formula for speed?

Back

Speed = Distance / Time.

Front

If a cyclist rode 3.75 miles in 0.3 hours, how fast was she going?

Back

12.5 miles per hour.

Front

How do you calculate the percentage of correct answers on a test?

Back

Percentage of correct answers = (Number of correct answers / Total number of answers) * 100.

Front

Chase got 36 correct and 14 incorrect answers on a test. What was the percentage of correct answers?

Back

72%.

Front

What does it mean if two quantities vary directly?

Back

It means that as one quantity increases, the other quantity also increases at a constant rate.