1. How many two-digit numbers N have the property that the sum of N and the number formed by reversing the digits of N is a perfect square ?
2. The square SAMF has an area of 169. It contains two over lapping squares. The smaller of these sqares has an area that is one quarter of the larger of them, and the erea of their overlap is 4. What is the erea of the shaded region ?
3. In the diagram, each of the integers 1 through 9 is to be placed in one circles, both horizontal and diagonal, add to 18. The 6 and 1 have been filled in as shown. Determine the value of the number represented by x in the diagram. Justify your answer
4. How many digits does the number 20¹³ have ?

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.

Câu hỏi 1:
The average of three numbers is 1988. The first number is 1984. The third number is 2 units more than the second number. Find the third number.

Câu hỏi 2:
The average of 5 consecutive odd numbers is 123. Find the greatest number.
Câu hỏi 3:
Which of the following fractions is equal to 2/3?

Câu hỏi 4:
The average of two numbers is 95. The first number is 2/3 of the second number. Find the first number
Câu hỏi 5:
Fill in the blank with the correct number: 6/100 kg = .... kg

Câu hỏi 6:
The sum of two fractions is 45/23 and the first fraction is one quarter of the second fraction. Find the first fraction.

Câu hỏi 7:
The sum of twonumbers is 463 and three are eighteen even numbers between these numbers. Find the greater number.

Câu hỏi 8:
Which of the following fractions is the greatest number?

Câu hỏi 9:
The average of two numbers is 95. The first number is 2/3 of the second number. Find these two numbers.

Câu hỏi 10:
The sum of the number of lions and monkeys in a zoo is 40 and lions are 1/3 the number of monkeys. How many monkeys are there in the zoo?