A.b . 129 c . 127d . 130
Solution: This kind of problem can be solved according to this formula.
16 1/( 1+ 1/5+ 1/25+ 1/ 125…………)= 16 1/ 1.25= 129
46. Three master workers, Zhang Qiang, AARON Li and Chong Wang, respectively processed 200 parts, and they started to work at the same time. After all the tasks of processing 200 parts in AARON Li were completed, Zhangjiang only processed 160 parts, and Chong Wang still had 48 parts unfinished. When Zhang Qiang finished the task of processing 200 parts, how many parts were left in Chong Wang? ( )
A.9 B. 10 C. 15 D. 25
Is the answer b?
Answer: Suppose the speed of Li Hui is one per minute.
Then Zhang Qiang's speed is 1.25 points/piece, and Wang is 25/ 19.
It takes 250 minutes to process 200 sheets.
At this time, Wang processed 190 pieces.
47. A school has three interest groups, sports, calligraphy and fine arts. It is known that 25 students, 24 students and 30 students participate in these three interest groups respectively. Five people participated in sports and calligraphy interest groups, two people participated in sports and art interest groups, and four people participated in calligraphy and art interest groups. 1 person participated in these three interest groups at the same time. Q: * * * How many people have joined the interest group? ( )
A.74 B. 72 C. 70 D. 69
The answer is D.
Solution: 25+24+30-5-2-4+ 1 = 69.