Skip to main content

Important Short Tips of Square Root ,Cube Root and Quant Quiz




















5. The least perfect square, which is divisible by each of 21, 36 and 66 is:
A. 213444
B. 214344
C. 214434      
D. 231444

6. How many two-digit numbers satisfy this property : The last digit (units digit) of the square of the two-digit number is 8 ?
A. 1
B. 2
C. 3
D. None of these

7.A group of students decided to collect as many paise from each member of group as is the number of members. If the total collection amounts to Rs. 59.29, the number of the member is the group is:
A. 57  
B. 67
C. 77  
D. 87

8. A group of students decided to collect as many paise from each member of group as is the number of members. If the total collection amounts to Rs. 98.01, the number of the member is the group is:
A. 101
B. 98
C. 99
D. 88

9.A man plants 49284 apple trees in his garden and arranges them so that there are as many rows as there are apples trees in each row. The number of rows is
A. 182
B. 202
C. 222
D. 122

10.If 0.13÷p^2=13, then p equals :
A. 0.01
B. 0.1
C. 10
D  100

ANSWER AND SOLUTION :




















6(D)Explanation :

A number ending with 8 can never become a perfect square
Let's examine this in detail
1 × 1 = 1
Hence, if the unit digit of a number is 1, unit digit of its square is 1
2 × 2 = 4
Hence, if the unit digit of a number is 2, unit digit of its square is 4
3 × 3 = 9
Hence, if the unit digit of a number is 3, unit digit of its square is 9
4 × 4 = 16
Hence, if the unit digit of a number is 4, unit digit of its square is 6
5 × 5 = 25
Hence, if the unit digit of a number is 5, unit digit of its square is 5
6 × 6 = 36
Hence, if the unit digit of a number is 6, unit digit of its square is 6
7 × 7 = 49
Hence, if the unit digit of a number is 7, unit digit of its square is 9
8 × 8 = 64
Hence, if the unit digit of a number is 8, unit digit of its square is 4
9 × 9 = 81
Hence, if the unit digit of a number is 9, unit digit of its square is 1
0 × 0 = 0
Hence, if the unit digit of a number is 0, unit digit of its square is 0



Comments

Post a Comment

Popular posts from this blog

Short Notes on Time and Distance

TIPS AND FORMULAS ON TIME AND DISTANCE: 1. Speed =   Distance/Time 2. Time =   Distance /Speed 3. Distance =  Speed x Time 4 . km/hr to m/s conversion: 1 kmph =   5/18 m/s 5.  m/s to km/hr conversion:   1 m/s =   18/5 m/s 6.  If the ratio of speeds of train A and B is a : b, then the ratio of time taken by them to cover the same distance =  b : a. 7.  If a man covers a certain distance at x km/hr and an equal distance at y km/hr. Then,the average speed during the whole journey is 2xy/(x + y) km/h 8 . The time taken by a train in passing a pole or standing man is the same as the time taken by the train to cover a distance equal to its own length. 9.  The time taken by a train of length 'L' metres in passing a stationary object of length 'B' metres is equal to the time taken by the train to cover a distance equal to  (L + B) m. 10.  If two trains are moving in the same directions at u m/s and v m...
Post a Comment
Read more

Quant Short Tricks for Fraction Problems

Let us study some of the common methods of identifying out the largest or smallest of a given set of fractions which are useful for Mental Maths.  Type – 1 When the numerators are same and the denominators are different, the fraction with the largest denominator is the smallest. Have a look at the following example. Example:   Which of the following fractions is the smallest? (3/5) , (3/7) , (3/13), (3/8) Here, 13 is the largest denominator, so, (3/13) is the smallest fraction. 5 is the smallest denominator, hence (3/5) is the largest fraction. Here logic is very simple,  Situation: (i)  Assume that you are 5 Children in your family. Your Dad brought an Apple and mom cut it into 5 pieces and distributed among all the children including you. (1/5) Situation (ii)  : Assume that you are 8 Children in your family. Your Dad brought an Apple and mom cut it into 8 pieces and distributed among all the children inclu...
Post a Comment
Read more

10 Fast Maths Tricks and Shortcuts

10 Fast Maths Tricks and Shortcuts Today I am going to summarise all the maths tricks that will speed up your calculation speed. I used them in CAT and IBPS exam. I am sure that these tricks will help you increase your score. I have written many articles in detail on these topics. Click on respective links to get details. List of Cool Maths Tricks Squaring In this simple trick, we need to modify the equation and make the units digit zero. After all, it is easy to multiply when units digit is zero. For example - Find square of 43 = (43+3) × (43-3) + (3×3) =(46×40) + 9 = (460×4) + 9 = 1840 + 9 = 1849 Finding Square of Any No. From 1 to 100   Pick Any No. Just like this: Multiplication Vedic maths gave us the easiest method to do complex multiplications quickly. This method can be quickly explained with an example. Multiply 62 with 32 Step 1 Step 2 Step 3 Multiplication with 5 Simply multiply the number by 10 a...
Post a Comment
Read more