Calculations
245 + 130 =
375
If you have 3 boxes and each box has 4 candies, how many candies are there in total?
3 × 4 = 12
A farmer has 3 buckets. Each bucket holds 10 liters. How many liters are there in total?
30 liters — straightforward.
It is 7:30 AM.
How many minutes to 8:00 AM?
30 minutes
Who is called the “Father of Geometry”?
Euclid
34 × 6 =
204
Tom, Lucy, and Max are sitting on a bench. Tom is not at the left end. Lucy is not in the middle. Who is in the middle?
Max is in the middle
If one monkey eats 1 banana in 2 minutes, how long will 2 monkeys take to eat 1 banana?
2 minutes — both can eat at the same time.
A movie starts at 5:15 PM and ends at 6:45 PM.
How long is the movie?
1 hour 30 minutes
What ancient civilization used hieroglyphs and early math?
Ancient Egypt
A rectangle has a length of 7 cm and width 3 cm. Find its area.
7 × 3 = 21 cm²
A farmer has chickens and cows. There are 14 heads and 38 legs. How many chickens and cows are there?
Chickens = 9, Cows = 5 (because 2×9 + 4×5 = 38 legs)
If it takes 5 machines 5 minutes to make 5 gadgets, how long would it take 1 machine to make 100 gadgets?
500 minutes — trick is to notice the rate per machine.
Tom leaves home at 8:20 AM.
He arrives at school at 8:55 AM.
How long is the trip?
35 minutes
What tool did ancient people use to count?
Abacus
1.5 hours into minutes
1.5 × 60 = 90 minutes
We boil one potato in 5 minutes. How many minutes do we need to boil 5 potatoes?
5 minutes — they all boil together.
You have a basket of eggs. If you take 2 eggs out, how many do you have?
2 eggs — you took them, so you “have” them.
A train leaves at 2:50 PM.
It arrives 1 hour 35 minutes later.
What time does it arrive?
4:25 PM
Which ancient civilization studied math to predict stars and time?
Babylonians
Find the perimeter of a rectangle with length 8 cm and width 4 cm
Perimeter = 2 × (8 + 4) = 2 × 12 = 24 cm
Some cats are in a basket. Every cat has 1 tail. How many tails do 0 cats have?
0 tails — trick is “zero cats”!
A father is 24 years older than his son.
How old is the son if the father is 3 times older than him?
Son is 12, father is 36
A school day starts at 8:10 AM.
There are 3 lessons, each lesson lasts 35 minutes.
Between each lesson there is a 10-minute break. What time does the school day end?
10:15 AM
Give me a place to stand, and I will move the Earth”?
Archimedes