What conjecture can you make about the sum of the first 10 odd numbers?

The sum 10 first odd numbers are:

1 + 3 + 5 + 7 + 9 + 11 + 13 + 15 + 17 + 19

You can see that the unit part of the numbers repeat, but in the latter 5 numbers we have:

1 + 3 + 5 + 7 + 9 + (10 + 1) + (10 + 3) + (10 + 5) + (10 + 7) + (10 + 9)

Now, we can rearrange this as:

2*(1 + 3 + 5 + 7 + 9) + 5*10

2*(23) + 5*10

now, every number multiplied by a 2, is an even number, and 5*10 = 50 is also an even number.

Here we can see that the sum of the first 10 odd numbers is an even number, and because is an even number different than 2, it is not a prime number.

You can solve the multiplications and get:

2*23 + 5*10 = 46 + 50 = 96

the total estimated nappy use.=10,500,000

step-by-step explanation:

given that on an average the average baby uses 3528 napkins.

in a particular year 2014, the number of births were 299697 in new south wales.

rounding off the number of births to the nearest hundred thousand we have

no of birtsh = 300000

also rounding off the average usage to nearst thousand we get

average use of a baby = 3500

hence total number of nappy estimated to be used = 3500x300000

= 10,500,000

answer is 10,500,000 nappies