What is the proportion not simplified also show work pls.

If olu is twice as old as funmi if the sum of their ages is 60 how old is olu

Assume that there is a 11% rate of disk drive failure in a year. a. if all your computer data is stored on a hard disk drive with a copy stored on a second hard disk drive, what is the probability that during a year, you can avoid catastrophe with at least one working drive? b. if copies of all your computer data are stored on four independent hard disk drives, what is the probability that during a year, you can avoid catastrophe with at least one working drive?

What is 6/10 rounded to the nearest half