Speed, Proportionality, and Scale Factors

This video covers Math 7 Unit 4 Lesson 2, focusing on ratios and rates with fractions. It begins with a number talk on mental division strategies, followed by a problem-solving session on train speed using ratios. The lesson then compares running speeds using fractions and explores scaling dimensions of the Mona Lisa for a notebook cover. The video concludes with homework problems and additional math exercises.

What is the main concept discussed in the number talk section?

• Multiplying fractions

• Finding quotients mentally

• Subtracting fractions

• Adding fractions

If a train travels 7.5 km in 6 minutes, how far does it travel in 1 minute?

• 1.75 km

• 2 km

• 1.5 km

• 1.25 km

What is the constant of proportionality when calculating the train's speed?

• 6/7.5

• 4/5

• 7.5/6

• 5/4

Who runs faster, Lynn or Noah?

• Lynn

• Noah

• Both run at the same speed

• Cannot be determined

How long does it take Lynn to run one mile at her speed?

• 8 minutes

• 9 minutes

• 10 minutes

• 11 minutes

What is the scale factor from the real Mona Lisa to its copy on the notebook?

• 11 to 30

• 10 to 21

• 9 to 11

• 7 to 10

What is the new diameter of a circle if the original diameter is 1.5 inches and the scale factor is 2?

• 3.5 inches

• 3 inches

• 2.5 inches

• 2 inches

How fast was the cyclist going if she rode 3.75 miles in 0.3 hours?

• 12.5 mph

• 15 mph

• 17.5 mph

• 10 mph

What is the cost per pound of ham if 1.75 lb costs $14.50?

• $8.28

• $9.50

• $10.25

• $11.00

How much water is needed if you have 9 quarts of grape juice in the recipe?

• 18 quarts

• 15 quarts

• 16 quarts

• 17 quarts