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How many 3-digit numbers divisible by 5 can be formed by using digits 0, 1, 2, 4, 5 without repetition?…

Given 10 points such that no 3 points are collinear. How many line segments can be counted in the figure…

John tosses a fair dice with 6 faces three times. In how many cases does the product of 3 faces…

In how many ways can we arrange 5 students and 1 teacher to form a line given that the teacher…

A box contains 100 marbles in 3 colors: red, blue and yellow. There are 20 red marbles and 50 blue…

How many rectangles are there in the figure below? Hỏi có bao nhiêu hình chữ nhật trong hình dưới đây?…

How many 3-digit numbers divisible by 4 can be formed by using the digits 1, 2, 3, 4, 6 and…

Given 20 different points on a plane, no three of which are collinear. How many triangles whose vertices are the…

A box contains 100 marbles in 3 colors: red, blue and yellow. There are 20 red marbles and 44 blue…

How many ways are there to arrange 4 boys and 2 girls sitting in a row that two ends of…