What is the next number in this matchsticks series riddle?

I have Rs.50 and I spend it in the way as below.

What numbers should go on the bottom line?
3 6 9 15
8 2 10 12
11 8 19 27
19 10 29 39
? ? ? ?

Find The Next Number In The Sequence

30 10 15 13 0 16 -15 ?

How many minutes are there in Feb 2017?

Note: The shortest answer is the correct answer.

What's the only room from which no one can enter or leave

A finger goes in me. You fiddle with me when you're bored. The best man always has me first. What am I?

Rearrange the letters in "new door" to make one word.

Three men in a cafe order a meal the total cost of which is $15. They each contribute $5. The waiter takes the money to the chef who recognises the three as friends and asks the waiter to return $5 to the men.

The waiter is not only poor at mathematics but dishonest and instead of going to the trouble of splitting the $5 between the three he simply gives them $1 each and pockets the remaining $2 for himself.

Now, each of the men effectively paid $4, the total paid is therefore $12. Add the $2 in the waiters pocket and this comes to $14. Where has the other $1 gone from the original $15?

Find the smallest sentence with all the English alphabet.