There are conversion tables everywhere that assist you in changing a different unit into another. Depending on what it is, you can also compare weight into water, cm into m and backwards.
824 just add all the sides so 12+12+400+400=824 and in simpler form w2+l2
Answer:
9
Step-by-step explanation:
3 times the sum of 4 and 2 = 3*(4+2)
= 3 * 6
= 18
18 - 9 = 9
7/10 in hundredths is 70/100
