WORD PROBLEMS INVOLVING MASS AND WEIGHT

The mass of an object is the amount of matter it contains.

Example 1 :

If one egg has a mass of 55 g, find the total mass of eggs in 50 cartons, each containing 12 eggs.

Solution :

Mass of 1 egg  =  55 g

Number of eggs in each carton  =  12

Total number of cartons  =  50

Total mass  =  55 x 12 x 50

=  33000 g

1000g  =  1 kg

=  33 kg

Example 2 :

Find the total mass of 32 chocolates, each of mass 28 grams.

Solution :

Number of chocolates  =  32

Mass of each chocolate  =  28 grams

Total mass  =  32 x 28

=  896 grams

Example 3 :

If a clothes peg has a mass of 6.5 g, how many pegs are there in a 13 kg box?

Solution :

Mass of 1 cloth peg  =  6.5 g

Mass of box  =  13 kg

1000 grams  =  1 kg

Converting kg to grams, we get

=  13000 grams

Number of pegs  =  13000/6.5

=  2000 pegs

Example 4 :

If a roof tile has mass 1.25 kilograms, how many tiles could a van with a load limit of 8 tonnes carry?

Solution :

1000 kg  =  1 tonne

8 tonnes  =  8(1000)

=  8000 kg

Mass of 1 roof tile  =  1.25 kg

Number of roof tiles carried by the van  =  8000/1.25

=  6400 tiles

Example 5 :

Find the total mass in tonnes of 3500 books, each with mass 800 grams.

Solution :

Mass of each book  =  800 grams

Total number of books  =  3500

Mass of 3500 books  =  800 x 3500

=  2800000 grams

1000 grams  =  1 kg

=  2800000/1000

=  2800 kg

1000 kg  =  1 tonne 

=  2800/1000

=  2.8 tonnes

Example 6 :

If the mass of 8000 oranges is 1.04 tonnes, what is the average mass of one orange?

Solution :

Total number of oranges  =  8000

Weight of oranges  =  1.04 tonnes

=  1.04 (1000)

=  1040 kg

=  1040(1000)

=  1040000 grams

Average weight of 1 orange  =  1040000 / 8000

=  130 grams

So, mass of 1 orange is 130 grams.

Example 7 :

Of all the planets in our solar system, Jupiter has the greatest gravitational strength.

a. If a 0.5 kg pair of running shoes would weigh 11.55 newtons on Jupiter, what is the strength of gravity there?

b. If he same pair of shoes weighs 0.3 newtons on Pluto, what is the strength of gravity on Pluto?

Solution :

Weight (W) = Mass (m) x gravity (g)

a. Solving for gravity = weight / mass

Weight = 11.55 newtons

mass = 0.5 kg

gravity = 11.55/0.5

= 23.1 m/s²

b. gravity = 0.3/0.5

= 0.6 newtons/kg

Example 8 :

Camille buys 1 package of ground beef and 4 bags of sugar. The mass of the beef is 1250 g and each bag of sugar weighs 600 g.

How much weight did Camille have to carry?

Express your answer in kilograms and grams.

Solution :

Mass = 1250 g

Weight of each sugar bag = 600 g

Number of bags = 4

Quantity of sugar in all 4 bags = 4(600)

= 2400 grams

Weight of Camille = 2400 + 1250

= 3650 grams

1 kg = 1000 grams

= (3000 + 650) grams

= 3 kg 650 grams

Example 9 :

Chef Teri ordered 4 sacks of skim milk and 3 sacks of cornstarch. Each sack of skim milk weighs 10.5 kg. How much skim milk did Chef Teri order?

Solution :

Weight of each sack of skim milk = 10.5 kg

Number of sacks of skim milk = 4

Weight = 10.5 (4)

= 42 kg

Example 10 :

A renovation company ordered sacks of cement and sand from a construction supplier. 325 kg 400 g of cement and 78 kg of sand had already been delivered, and they are still waiting for the other 215 kg 600 g of cement from the supplier. How many kilograms of cement did the company order altogether?

Solution :

Quantity of cement = 325 kg 400 g + 215 kg 600 g

= (325 + 215) kg + (400 + 600) grams

= 540 kg + 1000 grams

= 540 kg + 1 kg

= 541 kg

So, quantity of cement ordered is 541 kg.

Example 11 :

The weight of a cellphone is 130 grams, and a tablet is 65 grams heavier than the cellphone. The weight of a laptop is 1 kg 150 g. Which is heavier, 5 cellphones or 1 laptop? By how many grams?

Solution :

Weight of one cellphone = 130 grams

Weight of tablet = 130 + 65

= 195 grams

Weight of one laptop = 1 kg 150 grams

Converting into grams, we get

= 1000 g + 150 g

Weight of one laptop = 1150 grams

Weight of 5 cell phones = 5(130)

= 650 grams

Comparing these two weights, weight of 1 laptop is greater.

Kindly mail your feedback to v4formath@gmail.com

We always appreciate your feedback.