9514 1404 393
Answer:
32
Step-by-step explanation:
The first term is 5 and the common difference is 9-5=4, so the n-th term is ...
an = a1 +d(n -1)
an = 5 +4(n -1) = 4n +1
Then the term number for the term 129 is ...
129 = 4n +1 . . . . . put the given value in the formula
128 = 4n . . . . . . . subtract 1
32 = n . . . . . . . . . .divide by 4
The 32nd term is 129.
5x7=35
5x7=5x(5+2)
5x7=(5x3)+(5x4)
5x7=20+15
5x7=35
This is how I would do it :)
Answer:
A
Step-by-step explanation: You are correct!
Answer:
Is this the inter question
This is a typical radioactive decay problem which uses the general form:
A = A0e^(-kt)
So, in the given equation, A0 = 192 and k = 0.015. We are to find the amount of substance left after t = 55 years. That would be represented by A. The solution is as follows:
A = 192e^(-0.015*55)
<em>A = 84 mg</em>