The sum of integers from 1 to 100 that are di | vedclass

Name: PDF Generator App | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(b) The sum of integers from $1$ to $100$ that are divisible by $2$ or $5 =$ sum of series divisible by $2 +$ sum of series divisible by $5 -$ sum of

Vedclass · Accepted Answer

$3050$

Vedclass · Answer

(b) The sum of integers from $1$ to $100$ that are divisible by $2$ or $5 =$ sum of series divisible by $2 +$ sum of series divisible by $5 -$ sum of series divisible by $2$ and $5$.

$ = (2 + 4 + 6 + ...... + 100) + (5 + 10 + 15....... + 100)$

$ - (10 + 20 + 30 + ........ + 100)$

$ = \frac{{50}}{2}\left\{ {2 	imes 2 + (50 - 1)2} ight\} + \frac{{20}}{2}\left\{ {2 	imes 5 + (20 - 1)5} ight\}$

$ - \frac{{10}}{2}\left\{ {10 	imes 2 + (10 - 1)10} ight\}$

$ = 2550 + 1050 - 550 = 3050$.

The sum of integers from $1$ to $100$ that are divisible by $2$ or $5$ is

Similar Questions

Write the first three terms in each of the following sequences defined by the following:

$a_{n}=\frac{n-3}{4}$

Let $x_n, y_n, z_n, w_n$ denotes $n^{th}$ terms of four different arithmatic progressions with positive terms. If $x_4 + y_4 + z_4 + w_4 = 8$ and $x_{10} + y_{10} + z_{10} + w_{10} = 20,$ then maximum value of $x_{20}.y_{20}.z_{20}.w_{20}$ is-

Suppose that all the terms of an arithmetic progression ($A.P.$) are natural numbers. If the ratio of the sum of the first seven terms to the sum of the first eleven terms is $6: 11$ and the seventh term lies in between $130$ and $140$ , then the common difference of this $A.P.$ is

Consider a sequence whose sum of first $n$ -terms is given by $S_n = 4n^2 + 6n, n \in N$, then $T_{15}$ of this sequence is -

Jairam purchased a house in Rs. $15000$ and paid Rs. $5000$ at once. Rest money he promised to pay in annual installment of Rs. $1000$ with $10\%$ per annum interest. How much money is to be paid by Jairam $\mathrm{Rs.}$ ...................