1.
Write the greatest 4-digit number using different digits with 6 in the tens place.
Correct Answer
B. 9867
Explanation
The question asks for the greatest 4-digit number using different digits with 6 in the tens place. Looking at the options given, the number 9867 fits this criteria as it is the greatest number among the options and has 6 in the tens place. Therefore, 9867 is the correct answer.
2.
The predecessor of 80808080 is 80808081.
Correct Answer
B. False
Explanation
The predecessor of a number is the number that comes before it. In this case, the given number is 80808080. To find its predecessor, we need to subtract 1 from it. Therefore, the correct predecessor of 80808080 is 80808079, not 80808081. Hence, the answer is False.
3.
Look at the alphabets in the word KRISHNA, what fraction of alphabets are made of 3 line segments?
Correct Answer
B. 4/7
Explanation
In the word "KRISHNA," there are 7 alphabets in total. Out of these 7 alphabets, 4 alphabets (K, R, I, and A) are made of 3 line segments. Therefore, the fraction of alphabets made of 3 line segments is 4/7.
4.
In a garden, 1/7 are white roses, 4/7 are red roses and the rest are yellow roses. What fraction of the roses are yellow?
Correct Answer
B. 2/7
Explanation
The fraction of yellow roses can be found by subtracting the fractions of white and red roses from 1 (since the sum of all fractions should equal 1). Therefore, the fraction of yellow roses is 1 - 1/7 - 4/7 = 2/7.
5.
The LCM of 17 and 5 is:
Correct Answer
C. 85
Explanation
The LCM (Least Common Multiple) is the smallest multiple that is divisible by both numbers. In this case, the multiples of 17 are 17, 34, 51, 68, 85, 102, and so on. The multiples of 5 are 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, and so on. The smallest multiple that appears in both lists is 85, so it is the LCM of 17 and 5.
6.
41 and 43 are _______________numbers.
Correct Answer
twin prime, twin primes, Twin Primes, Twin primes, Twin Prime
Explanation
41 and 43 are twin primes because they are both prime numbers and their difference is 2. Twin primes are pairs of prime numbers that are only two units apart from each other. In this case, both 41 and 43 are prime numbers, and their difference is indeed 2, making them a pair of twin primes.
7.
Which one of the following is the prime factorization of 140?
Correct Answer
C. 2 X 2 X 5 X 7
Explanation
The prime factorization of a number breaks it down into its prime factors. In this case, 140 can be broken down into 2 x 2 x 5 x 7. This means that 140 is divisible by 2, 2, 5, and 7, and these are its prime factors.
8.
Identify the HCF of the first even number and the fifth composite number.
Correct Answer
D. 2
Explanation
The highest common factor (HCF) is the largest number that can divide evenly into two or more numbers. In this case, we are asked to find the HCF of the first even number and the fifth composite number. The first even number is 0, and the fifth composite number is 10. The factors of 0 are 0, and the factors of 10 are 1, 2, 5, and 10. The only number that appears in both lists is 2. Therefore, the HCF of 0 and 10 is 2.
9.
How many lines can be drawn passing through a given point?
Correct Answer
B. Infinite
Explanation
A given point can be used as a starting point to draw an infinite number of lines. This is because a line can be extended indefinitely in both directions from the given point. Therefore, there is no limit to the number of lines that can be drawn passing through a given point.
10.
The angle between two opposite rays is:
Correct Answer
C. Straight
Explanation
The angle between two opposite rays is straight. This is because opposite rays form a straight line, and a straight line creates an angle of 180 degrees. Therefore, the correct answer is straight.
11.
What part of a revolution have you turned through if you stand facing south and turn clockwise to face east?
Correct Answer
A. 3/4 revolution
Explanation
If you start facing south and turn clockwise to face east, you have turned through 3/4 of a revolution. This is because a full revolution is 360 degrees, and turning from south to east is a 90-degree turn. So, if you divide 90 degrees by 360 degrees, you get 1/4. Subtracting 1/4 from 1 gives us 3/4, indicating that you have completed 3/4 of a revolution.
12.
Which of the following numbers is co-prime?
Correct Answer
B. 8, 15
Explanation
Two numbers are said to be co-prime if their greatest common divisor (GCD) is 1. In this case, the GCD of 8 and 15 is 1, which means they are co-prime. Therefore, the correct answer is 8, 15.
13.
The complement angle of 78^{0} is:
Correct Answer
D. 12^{0}
Explanation
The complement angle of a given angle is the angle that, when added to the given angle, equals 90 degrees. In this case, the complement angle of 780 degrees would be 90 - 780 = -690 degrees. However, since angles are usually measured between 0 and 360 degrees, we can add 360 degrees to -690 to find the equivalent positive angle, which is 360 - 690 = -330 degrees. Therefore, the complement angle of 780 degrees is 360 - 330 = 30 degrees.
14.
The reciprocal of 1/4 x 2/3 is:
Correct Answer
C. 6
Explanation
The reciprocal of a fraction is obtained by flipping the numerator and denominator. In this case, the reciprocal of 1/4 x 2/3 would be 3/2 x 4/1, which simplifies to 6.
15.
If 45/60 is equivalent to 3/x, what is the value of x?
Correct Answer
A. 4
Explanation
To find the value of x, we can cross multiply the fractions. Cross multiplying 45/60 and 3/x gives us 45x = 180. Dividing both sides by 45, we find that x = 4.