Given 100 points with any 3 points non-aligned. Draw all the line passing through any 2 of these points. How many lines are there?
With 100 points, then we draw are:
100 x 99 : 2 = 4950 ( lines )
Answer: 4950 lines
Given that 4 points A, B, C, D are on the same line. How many segments are there?
Câu 1 :Each of cars can take 8 people. How many cars needed to take 124 people?
Câu 2 : How many integer numbers between 200 and 300 are there for which the hundreds digit equals the sum of the other two digits?
Câu 3 : The average of five numbers is 20. The average of the five number is 18 when one of the numbers is chaned to 4. What is the orginal value of the changed number?
Câu 4 :A book has 250 pages starting at number 1. How many digits are there in the page numbers of the book?
Câu 5 : Find A, if A is 3 less than the average of 48; 55; 29 and A. The value of A is…
Câu 6 : The sum of denominator and numerator of a fraction is 121 and the fraction is equal to 4/7. Find the denominator of the fraction?
Câu 7 : The sum of two numbers is equal to 77. If the first number is multiplied by 8 and the second by 6, the two product are equal. The larger of these numbers is…
Câu 8 : Which is the greatest 2 - digit number divisible by 2, 3 and 4?
Câu 9 : Calculate: (1 + 2/5) x 6/7.
Câu 10 : Give the number sequence: 1, 4, 7, 10, 13, … Find the 15th term of the number sequence.
Given that . How many divisors does the number A have?
Câu 31:
Given that the set .\(A=\left\{x\in N\left|x⋮3,2\le x\le999\right|\right\}\)
How many elements are there in the set A?
Answer: ...
A flight of stairs has 9 steps. Alice can go up for 1 step or 3 steps each time. How many
ways are there for Alice to go up the stairs?
How to do that?
Toán tiếng anh:
Several different numbers are written on the board. Exactly two them are divisible by 3 and exactly 9 of them are divisible by 13. Let M be the greatest of these numbers. What is the smallest possible value of M?
How many apples would you get from the 10th tree if a farmer notices a pattern from picking the apples on the 1st through the 10th tree. He picked 4 from the first tree, 7 from the second tree and 10 from the third tree.
Answer:
A box coutains 15 identical reams paper. The total mass of the box with 1/5of all the reams of paper. The mass of the emty box is 2/7 of a reams of paper . What í the mass of the emty box
