40
Practical tasks
Textbook: Part 2, lesson 40, pp. 4–6
GoalPractical tasks: calculations with kilocalories and mass.
New words
kilocalorie (kcal) · kilokaloriyadaily menu · ratsionmass · massain total · jami
Explanation
We need arithmetic every day. The energy in food is measured in kilocalories (kcal). To find the energy of a whole day we add the kcal of all meals. For equal items we first find one item and then multiply by the number we need.
Worked examples
Breakfast 450 kcal, lunch 650 kcal, dinner 400 kcal: 450 + 650 + 400 = 1 500 kcal.
5 equal loaves weigh 1 000 g, so 1 loaf is 1 000 : 5 = 200 g and 8 loaves are 200 × 8 = 1 600 g.
Class activity
“A one-day menu”: children write favourite dishes with their kcal values (given by the teacher) in a table and calculate the total for one day.
Practice
1
Breakfast is 450 kcal, lunch 650 kcal, dinner 400 kcal and an afternoon snack 150 kcal. How many kcal in the whole day?
1650
2
4 equal biscuits give 480 kcal. How many kcal do 7 biscuits give?
840
3
A bakery uses 45 kg of flour a day. How many kg does it use in 6 days?
270
4
Notebooks weigh 3 200 g and books 2 800 g. How many g is the load in the bag (without the bag itself)?
6000