#1.) A rational number is a number that can be written as a ratio. That means it can be written as a fraction, in which both the numerator (the number on top) and the denominator (the number on the bottom) are whole numbers. The number 8 is a rational number because it can be written as the fraction 8/1.
I don't want to give you the answer cause that will not help you I'm the future If I just give it to you. It might help you but that's what I learned in school is that it doesn't help. Because like if you cheat on a test you won't get to learn. But if you did it yourself and got it wrong you can see why
The interest rate is 4<span />
600 in3
Work:
8•15
120•10
1200/2
=600in3
The factorial ! just means we multiply by every natural number less that the value so
6! =6×5×4×3×2×1= 720
for permutations we use the formula n!/(n-r)!
so we have 8!/(8-5)!=8!/3!=8×7×6×5×4
for combinations s we have n!/(n-r)!r!
so we have 12!/(12-4)!4!=12!/8!4!=12×11×10×9/4×3×2=11×10×9/2=99×5