The easiest examples
- Three cats
If three cats eat three mice in three minutes, after which time 140 cats eat 140 mice?
Is the number 146025 divisible by 6?
Ivan bought 7 same chocolates for 28 Eur. How many euros he pay for 21 chocolates?
- One half
One half of ? is: ?
What is better for people (employees)? ?
One brick is 6 kg and half a brick heavy. What is the weight of one brick?
The parents had 3 daughters. Each of them had one brother. How many members family had?
7 trees in 5 lines grows in the orchard. How many trees are in the orchard?
I have 18 balls and my friend has 32. About how many has my friend more balls?
A cyclist passes 88 km in 4 hours. How many kilometers he pass in 8 hours?
- Proof PT
Can you easy prove Pythagoras theorem using Euclidean theorems? If so, do it.
Compare fractions ?. Which fraction of the lower?
- Reverse Pythagorean theorem
Given are lengths of the sides of the triangles. Decide which one is rectangular: Δ ABC: 77 dm, 85 dm, 36 dm ? Δ DEF: 55 dm, 82 dm, 61 dm ? Δ GHI: 24 mm, 25 mm, 7 mm ? Δ JKL: 32 dm, 51 dm, 82 dm ? Δ MNO: 51 dm, 45 dm, 24 dm ?
- Is right?
Is triangle with sides 51, 56 and 77 right triangle?
From which law follows directly the validity of Pythagoras' theorem in the right triangle? ?
- 7 heroes
5 heroes galloping on 5 horses behind. How many ways can sort them behind?
Calculate how many hours take holidays, if take 7 weeks.
Compare with characters >, <, =: 85.57 ? 80.83
In how many ways can 5 shuttle vans line up at the airport?
The root of the equation ? is: ?