Well, It would be hard to write out the formula and everything here so I wrote it out for you! Work shown!
I think 20×5=100 then 100÷2
if we look on one side, we already have one measurement. 4 cm. ok, that's the measurement on that side. look to the left now. that other side is also the same length, so we take that number and multiply it be 2 to get

Wait! we're not done yet. look at the top. do you see the 3? well that's the width for the top of the rectangle. the bottom must be the same to right? so we get

add both equations and you get

The answer is 14cm! Don't forget to label. ;)
22x12x5 and you will get the answer
Answer:
12 days.
Step-by-step explanation:
I looked at it this way:
He has to take 4/28 pills the first day, so it's 28-4=24. Then I divided 24 by 2.
In simpler terms:
28-4=24
24/2
12