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Problems: finding the whole
Textbook Part 3, pp. 14–15
GoalWhen the parts are known, find the whole by adding.
New words
whole · butunpart · qismdrone · dronkilogram (kg) · kilogramm (kg)
Explanation
Part + part = whole. When a problem gives two (or more) parts and asks for the whole, we add the parts. In a diagram the parts are drawn as pieces of the whole bar.
Worked examples
A drone carried loads of 12 kg and 15 kg. Total: 12 + 15 = 27 kg. 27 < 30, so the big drone can lift it.
[——23——|——33——] = ? → 23 + 33 = 56
Class activity
“Choose a drone for the farmer”: three drone cards (price, lifting power, battery time). Pairs choose the best one and explain why.
Practice
1
Parts 34 and 25. Whole?
59
2
40 sheep graze in one field and 35 in another. How many in all?
75
3
23 + 33 = ?
56
4
On a scale: duckling + 2 kg weight = 5 kg. How heavy is the duckling?
3