Heather is collecting dimes. She saves one dime on the first day, two dimes on second day, and three dimes on third day. If this pattern continues, hom much money will heather have saved at the end of 30 days? Please Explain!

hope dis help ;_;

Step-by-step explanation:

It's easy to see the manual solution: 1(.1) + 2(.1) + 3(.1) ++ 30(.1).

But nobody wants to do that repetitive computation. If we factor out the (.1),

we see (.1) * (1+2+3+4...+30). Still somewhat repetitive, but not bad for just 30.

We really need a formula for big numbers though. The short cut for adding a series

of numbers is to find the average of the first and last numbers and multiply by how

many there are in the list:

(first + last)(the quantity of numbers) / 2 = (1 + 30)(30) / 2 = 465

465(.1) = $46.50

90

Step-by-step explanation:I think it 90 because 1+2+3+4+5= 15 so 15x6= 90

probability for j is 1/4

while

a is 1/6