1. Find the sum of all consecutive numbers from 1 to 15

Solution:

15 x next number - 16 then divide by 2

15 x 16 = 240 / 2 = 120

2. Find the sum of all consecutive numbers from 1 to 100

Solution:

100 x 101 = 10,100 / 2 = 5,050

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3. Find the sum of all odd consecutive numbers from 1 TO 20

get half of 20 which is 10 then square it = 100

4. Find the sum of all odd consecutive numbers from 1 TO 60

get half of 60 which is 30 then square it = 900

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5. Find the sum of all EVEN consecutive numbers starting from  2 to 35

35 is not even so need to bring it down to 34 then divide by 2 = 17 EVEN CONSECUTIVE NO. Then multiply 17 by next number 18 

17 x 18  = 306


6. Find the sum of all EVEN consecutive numbers starting from  2 to 58

SINCE 58 is even then divide by 2 = 29

then multiply 29 to the next number which is 30 = 870




7. Find the 12 consecutive EVEN numbers whose sum is 468
      
12/468 = 39 (odd put in between of 38 and 40 above)


28 30 32 34 36 38 40 42 44 46 48 50