Amit built a sand castle that measured 151 centimeters by 159 centimeters, and dug a moat around it. Afterward, they decided to change the castle size, making it 127 centimeters by 233 centimeters.
How much longer will the new moat be than the old one?

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?