David was trying to sleep one night but there was too much noise around him? his clock ticked every 5 seconds , a tap was dripping every 7 seconds and his pet dog snored every 12 seconds he noticed n his clock that all three things happened together on the stroke of midnight (a) after how many second would all three things happen together again. (b) how many times would all three things happen together again between midnight and one o'clock

A) 420 seconds = 7 minutes

B) 8 times

Step-by-step explanation:

A) After how many second would all three things happen together again?

Solution:

His clock ticked every 5 seconds , a tap was dripping every 7 seconds and     his pet dog snored every 12 seconds. It all happens simultaneously = 5*7*12=420 seconds

B) How many times would all three things happen together again between    midnight and one o'clock

Since all these events happen together after every 420 sec = 7 mins and there are 60 mins between midnight and 1 o'çlock , thus 60/7 = 8 times

he used the algebra tiles correctly.

step-by-step explanation:

given : 3x(2x-1)

solution :

since he used algebra tiles .

armando's solution is the same in the solution shown in figure

as he distributed 2x into x and x and wrote them vertically

and also write   -1 vertically

and 3x into x and x and x and wrote it horizontally

performing the multiplication in the algebra tiles we get

and solving the given expression :

3x(2x-1)

since solving the expression using tiles   and solving the expression algebraically we get the same answer

thus   we can choose the first statement as the answer to this problem which is "he used the algebra tiles correctly".

1. 22

2. 1

3. 7

4. 18

step-by-step explanation

e2020 got it right