# Reason - 9th grade (14y) - math problems

#### Number of problems found: 474

- Tricolors

From the colors - red, blue, green, black and white, create all possible tricolors. - Two-element combinations

Write all two-element combinations from elements a, b, c, d. - Six on dice

What is the probability that when throwing two dice will fall at least one six? - Probability

How probable is a randomly selected three-digit number divisible by five or seven? - Chess

How many different ways can initiate a game of chess (first pass)? - Diofant equation

250x + 120y = 5640 - One three

We throw two dice. What is the probability that max one three falls? - Lines

In how many points will intersect 14 different lines, where no two are parallel? - Subsets

How many 19 element's subsets can be made from the 26 element set? - Algebrogram

Solve algebrogram: mama+anna=vari How many solutions are? - Consecutive numbers

Sum of ten consecutive numbers is 105. Determine these numbers (write first and last). - Bookshelf and books

How many ways can we place 7 books in a bookshelf? - The dice

What is the probability of events that if we throw a dice is rolled less than 6? - Coins

On coins found was stated that from the year 87 BC. It is right? - Dice

How many times must throw the dice, the probability of throwing at least one six was greater than 90%? - Seating

How many ways can 6 people sit on 6 numbered chairs (e. g. , seat reservation on the train)? - Three-digit

How many do three-digit natural numbers not have the number 7? - Progression

-12, 60, -300,1500 need next 2 numbers of pattern - Right

Determine angles of the right triangle with the hypotenuse c and legs a, b, if: ? - Hexagon = 8 parts

Divide the regular hexagon into eight equal parts.