1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
vekshin1
3 years ago
7

The sum of all positive integers less than 400 which are divisible by 5. Can someone give me the steps to do this?

Mathematics
1 answer:
IceJOKER [234]3 years ago
3 0

Answer:

Sum of all positive integers less than 400 and divisible by 5 is 15,800.

Step-by-step explanation:

TO FIND :

The sum of all positive integers less than 400 which are divisible by 5.

The set of positive integers I^+  =  1,2,3, 4,5,6,7,.........,,

Now, the number should be divisible by 5.

SO, the desired set of positive integers =  { 5,10,15,20,.......}

Again the numbers are LESS than 400.

So, the desired set of positive integers =  { 5,10,15,20,....... 385,390, 395}

Here, First term a  = 5, common difference d  = 4 and last term an = 395

a_n = a+ (n-1) d\\\implies 395 = 5 + (n-1) 5\\\implies 78 = n - 1 \implies n =  79

⇒There are total 79 terms in the series.

So, SUM OF 79 TERMS  =

S_n = \frac{n}{2} (a + a_n) \\\implis S_{79} = \frac{79}{2} (5 + 395)  = 15,800\\\implies S_{79} = 15,800

Hence, The sum of all positive integers less than 400 which are divisible by 5 is 15,800.

You might be interested in
1/2t + 25; -10 PLEASE HELP
makkiz [27]
You need it to be solved?

4 0
3 years ago
Solve equation 13=x/7+5
yuradex [85]

Answer:

56

Step-by-step explanation:

Isolate the variable (x). Note the equal sign, what you do to one side, you do to the other. Do the opposite of PEMDAS.

First, subtract 5 from both sides:

13 (-5) = (x/7) + 5 (-5)

13 - 5 = x/7

8 = x/7

Isolate the variable x. Multiply 7 to both sides:

8(7) = (x/7)(7)

8(7) = x

x = 8 * 7

x = 56

56 is your answer for x.

~

3 0
3 years ago
Read 2 more answers
Is the set closed or not closed under operation? Negative Integers under multiplication
Nutka1998 [239]

The set is not closed

Example

-4 * -2 = 8

8 is not a negative integer

8 0
3 years ago
I need help to these questions. Convert these fractions to a decimal 7/8 , 4 3/8. Thanks
ehidna [41]
Simple...

you have: \frac{7}{8} and 4 \frac{3}{8}

Now, the first one is easy just divide it...

\frac{7}{8} =0.875

Now....

4 \frac{3}{8}    needs to be converted...

Multiply the whole number*denominator...

4*8=32

Now add the numerator....

32+3=35

Now use the original denominator...

\frac{35}{8}

Now divide...

\frac{35}{8}=4.375


Thus, your answer.
7 0
3 years ago
Read 2 more answers
Renee can see a 25 square foot quilt in 16 hours. Genera can sew the same size quilt in 12 hours. How long would it take them to
scoundrel [369]

28 hours because they are too long from each other

3 0
3 years ago
Read 2 more answers
Other questions:
  • What three simpler multiplications can you use to find 8 x 242?
    9·1 answer
  • If the measures of two angles add up to 90
    15·1 answer
  • Explain how to write a function rule from the table below.<br><br> x :2 4 6<br> y :1 0 –1
    11·2 answers
  • Pls click the screnshot
    9·1 answer
  • 5. Each year a tree farm grows 40 more trees than the number of trees grown the previous year. The farm sells all of their trees
    10·1 answer
  • Using a spectrometer, a sample was analyzed to have a percent transmittance of 85%. what percentage of light was actually absorb
    5·1 answer
  • Choose the expression that completes the equation. 33 ÷ 3 + 10 =______
    15·1 answer
  • Can someone please help
    14·1 answer
  • Your portfolio value has grown from 2500 to 3800 what is the percent of the growth rate
    9·2 answers
  • Pls help due soon!! (no scam answers or links) :)
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!