12 question: (1):28/ 5 = 140 (pieces)
(2): 80/( 1-4/5) =8* (times) 5=400 (weeks)
13 Question: 1804/ 39/40 is approximately equal to 1850 (ten thousand tons).
14 question: 9000/( 1- 46) =9200 (ten thousand people)
Titles in the green box: 1: one tenth, one fortieth, one eightieth. (Skill: Molecules /2)
2: 8 1 of 32 people and 64% of 243 people. (Skill: numerator *2, denominator *3)
That's right! I wish you progress in your grades!