Alex and Jack work for a computer software company. Alex can write a computer program in 24 hours, while
Jack can write it in 16 hours. How long will it take them to write the program together?
Answer: 9.6 hours
Answer:
I hope attached image will help you!
They both have 5 in common
if you were to reduce the fraction it would be 11/16 because
55 divided by 5 is 11 and 80 divided by 5 is 16
Part A is irrational, but Parts B and C are both rational.
We know that Part A is irrational because an irrational number added to a rational number is still irrational. Also, an irrational number multiplied by a rational number is still irrational.
With Part B, we have an irrational number in the square root of 7. However, it is then squared to give us 7. This leaves us with 7 times a^2 which is rational. Two rational numbers multiplied still give us a rational number.
Finally, Part C only involves adding and multiplying rational numbers. Since that can only yield rational numbers, it must be rational.