The polygon that when rotated at 180 degrees about it's center may not be carried onto itself is a quadrilateral. The reason being quadrilateral is not regular in the sense that different sides have different measures.
For this case we have an equation of the form:
y = A * (b) ^ t
Where,
A: initial amount
b: decrease factor
t: time
Substituting values:
y = 30 * (b) ^ t
To calculate t we use a point in the table.
We have:
(t, y) = (1, 28.5)
Substituting:
28.5 = 30 * (b) ^ 1
b = 28.5 / 30
b = 0.95
Answer:
a. Decay factor is 0.95
In a four-digit number, the first digit cannot be 0, so there are only 4 even numbers available. For the second, third, and fourth digits, there are 5 available numbers. Thus, the number of 4-digit numbers containing only even digits is 4 x 5 x 5 x 5 = 500 numbers.
