Advertisements
Advertisements
प्रश्न
The sum of the multiplication table of natural number ‘n’ is given by 55 × n. Find the sum of table of 7.
Advertisements
उत्तर
Given, the sum of multiplication table of n natural numbers = 55 × n
Sum of table of 7 = 55 × 7 ...[Put n = 7]
= 385
APPEARS IN
संबंधित प्रश्न
Observe the patterns of digits made from line segments of equal length. You will find such segmented digits on the display of electronic watches or calculators.
If the number of digits formed is taken to be n, the number of segments required to
form n digits is given by the algebraic expression appearing on the right of each pattern.
How many segments are required to form 5, 10, 100 digits of the kind −
Use the given algebraic expression to complete the table of number patterns.
| S. No |
Expression |
Terms | |||||||||
| 1st | 2nd | 3rd | 4th | 5th | ... | 10th | ... | 100th | ... | ||
| 1 | 2n - 1 | 1 | 3 | 5 | 7 | 9 | - | 19 | - | - | - |
| 2 | 3n + 2 | 5 | 8 | 11 | 14 | - | - | - | - | - | - |
| 3 | 4n + 1 | 5 | 9 | 13 | 17 | - | - | - | - | - | - |
| 4 | 7n + 20 | 27 | 34 | 41 | 48 | - | - | - | - | - | - |
| 5 | n2 + 1 | 2 | 5 | 10 | 17 | - | - | - | - | 10001 | - |
Write down the following in the product form: 10a3b3c3
If 11 is subtracted from 4 times a number, the result is 89. Find the number.
When Raju multiplies a certain number by 17 and adds 4 to the product, he gets 225. Find that number.
Find two numbers such that one of them exceeds the other by 18 and their sum is 92.
One out of two numbers is thrice the other. If their sum is 124, find the numbers.
The sum of two consecutive even numbers is 74. Find the numbers.
Reena is 6 years older than her brother Ajay. If the sum of their ages is 28 years, what are their present ages?
Mrs. Goel is 27 years older than her daughter Rekha. After 8 years she will be twice as old as Rekha. Find their present ages.
The perimeter of the triangle shown in the following figure is ______.
If m is a whole number, then 2 m denotes a multiple of 2.
The additive inverse of an integer x is 2x.
If x is a negative integer, – x is a positive integer.
To find sum of three numbers 14, 27 and 13, we can have two ways:
- We may first add 14 and 27 to get 41 and then add 13 to it to get the total sum 54 or
- We may add 27 and 13 to get 40 and then add 14 to get the sum 54. Thus, (14 + 27) + 13 = 14 + (27 + 13)
This can be done for any three numbers. This property is known as the associativity of addition of numbers. Express this property which we have already studied in the chapter on whole numbers, in a general way, by using variables a, b and c.
The side length of the top of square table is x. The expression for perimeter is ______.
The sum of first n natural numbers is given by `1/2n^2 + 1/2n`. Find the sum of first 5 natural numbers.
If 
= 2x + 3, 
= `3/2x + 7` and 
= x – 3 then find the value of:
2
+ 
– 
If 
= `3/4x - 2` and 
= x + 6, then find the value of:
– 
If = `3/4x - 2` and = x + 6, then find the value of:
2
– `3/2`
