12.40 am is the next time they both ring at the same time
This is a right triangle
the missing is the hypotenuse = √(6² + 8² ) = √100 = 10
The correct answer is the second
hello
to solve this question, we need to use know the number of possible outcomes

let's find the number of possible outcomes
we have four tiles numbered 1, 4, 5 and 8
possible outcomes are
The period of y = 4 cos(8πx) is 2π/(8π) = 1/4, since
cos(x - 2π) = cos(x)
and if we replace x with 8πx, we get
cos(8πx - 2π) = cos(8πx)
and
8πx - 2π = 8π (x - 1/4)