Three bells ring at an interval of 10,20,and 30 minutes respectively. If they all ring together at 10:30 p. m.,at what time will they again ring together?

11:30 PM

Step-by-step explanation:

This question is essentially asking for the lowest common multiple of 10, 20, and 30. If we write out all the multiples of each, we get:

10: 10, 20, 30, 40, 50, 60, 70, ...

20: 20, 40, 60, 80, ...

30: 30, 60, 90, ...

As you can see, the lowest common multiple is 60, and 60 minutes after 10:30 PM is 11:30 PM.

she was supposed to add the hours(38.5) and multiply the amount of money she earned(7.50) resulting in $288.75 .

correct me if i'm wrong and if it is i'm truly sorry.

answer: the proof is mentioned below.

step-by-step explanation:

since, given:   lines bc = ef

prove:   lines ac > ef

          statements                                           reason

1. bc=ef                                           1. given

2. ac= ab+bc                                 2. because b is the point between the  

                                                            line segment ac

3.   ac > bc                                       3. because if a line segment is equal to

                                                          the sum of two line segments then it is

                                                          always greater then each of these

                                                          individual line segments

4. ac > ef                                         4. by equality property.