Mary Jane's Rate Growing Post

Rate Growing Post: Part 1

Definitions:

Ratio: compares two quantities measured in the same unit

Rate: compares two quantities measured in different units

The difference between rate and ratio is that the quantities in a rate is measured in different units while the quantities in a ratio is measured in the same unit.

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5. What is the unit rate in each?

a) A blue whale eats 8 t of krill in 2 days.

The unit rate is 4 t/day.

b) The cruising speed of a blue whale allows it to travel 193 km in 10 h.

The unit rate is 19.3 km/h.

c) A bull moose bellows 15 times in 2 1/2 h.

The unit rate is 6 bellows/h.

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13. The table shows driving information for three drivers. Metric fuel consumption is measured in L/100 km, or litres per kilometre.

a) What is the fuel consumption for Sarah’s vehicle in litres per kilometre? Give your answer to four decimal places.

The fuel consumption for Sarah's vehicle in litres per kilometre is 0.0714 L/km.

b) How could you change the answer in part a) to express it in L/100 km?

To change answer in part a) so that it expresses it in L/100 km, you need to multiply 1 km by 100 and since your multiplying that by 100 you need to do the same for the litres.

c) Which driver’s vehicle had the lowest fuel consumption?

Joe's vehicle had the lowest fuel consumption because:

Sarah's vehicle: 60/840 = 0.0714 L/km

Joe's vehicle: 28/400 = 0.0070 L/km

Martin's vehicle:20/245 = 0.0816 L/km

Based on this, Joe's vehicle seemed to have the lowest fuel consumption.

Coin Math Question:

What is the rate for coins per person if there were 1300 coins in a jar (American currency) and the coins were divided among 100 people?

The rate would be 13 coins/person.

1300/100 = 13 coins.

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Part 2

This is a recipe for spaghetti sauce that serves 4 people.

1) What would the recipe look like if it had to serve 10 people? Show your calculations.

To rewrite the recipe so that it serves 10 people, you have to multiply each ingredient by 2.5 because to get from 4 people to 10 people, you multiply by 2.5.

Calculations:

1/2 lb ground beef x 2.5 = 1 1/4 lb ground beef

1 medium onion diced x 2.5 = 2 1/2 medium onion diced

1 celery finely sliced x 2.5 = 2 1/2 celery finely sliced

1 clove garlic x 2.5 = 2 1/2 clove garlic

14 oz can of tomatoes chopped x 2.5 = 35 oz can of tomatoes chopped

1/2 can of tomato paste x 2.5 = 1 1/4 can of tomato paste

1 tsp parsley x 2.5 = 2 1/2 tsp parsley

1 1/2 tsp basil x 2.5 = 3 3/4 tsp basil

1 tsp oregano x 2.5 = 2 1/2 tsp oregano

1 tsp sugar x 2.5 = 2 1/2 tsp sugar

1/2 tsp Worchestershire Sauce x 2.5 = 1 1/4 tsp Worchestershire Sauce

1/2 tsp seasoning salt x 2.5 = 1 1/4 tsp seasoning salt

1 bay leaf x 2.5 = 2 1/2 bay leaf

Revised spaghetti sauce recipe (serves 10 people):

1 1/4 lb ground beef

2 1/2 medium onion diced

2 1/2 celery finely sliced

2 1/2 clove garlic

35 oz can of tomatoes chopped

1 1/4 can of tomato paste

2 1/2 tsp parsley

3 3/4 tsp basil

2 1/2 tsp oregano

2 1/2 tsp sugar

1 1/4 tsp Worchestershire Sauce

1 1/4 tsp seasoning salt

2 1/2 bay leaf

2) What would the recipe look like if you had to only serve 1 person? Show your calculations.

To rewrite the recipe so that now it serves only one person, you have to divide each ingredient by 4 because to get from 4 people to 1 person you divide by 4.

Calculations:

1/2 lb ground beef /4 = 1/8 lb ground beef
1 medium onion diced /4 = 1/4 medium onion diced
1 celery finely sliced /4 = 1/4 celery finely sliced
1 clove garlic /4 = 1/4 clove garlic
14 oz can of tomatoes chopped /4 = 3 1/2 oz can of tomatoes chopped
1/2 can of tomato paste /4 = 1/8 can of tomato paste
1 tsp parsley /4 = 1/4 tsp parsley
1 1/2 tsp basil /4 = 0.375 / 7.5ml tsp basil
1 tsp oregano /4 = 1/4 tsp oregano
1 tsp sugar /4 = 1/4 tsp sugar
1/2 tsp Worchestershire Sauce /4 = 1/8 tsp Worchestershire Sauce
1/2 tsp seasoning salt /4 = 1/8 tsp seasoning salt
1 bay leaf /4 = 1/4 bay leaf

Revised spaghetti sauce recipe (serves 1 person):

1/8 lb ground beef

1/4 medium onion diced

1/4 celery finely sliced

1/4 clove garlic

3 1/2 oz can of tomatoes chopped

1/8 can of tomato paste

1/4 tsp parsley

0.375/7.5 ml tsp basil

1/4 tsp oregano

1/4 tsp sugar

1/8 tsp Worchestershire Sauce

1/8 tsp seasoning salt

1/4 bay leaf