a) 1 2 3 4 5 6 7 8 9=81
b) 1 2 3 4 5 6 7 8 9=48
c) 1 2 3 4 5 6 7 8 9=99
d) 1 2 3 4 5 6=76
2) 3 children spend 3 minutes to make 3 paper flower. If 7 children spend 7 minutes to
make paper flowers, find the number of paper flowers at most that they can make.(Assume that each child spends equal time for making a paper flower)
3) In a certain city, the ratio of male and female is 8:7 . The average age of male is 35
years old while the average age of female is 32 years old. Find the average age of the
whole population.
4) In a Mathematics competition, there are 5 questions.
Candidate A answers Question 1,2,3 and 4 correctly, he gets 26 marks.
Candidate B answers Question 1,2,3 and 5 correctly, he gets 25 marks.
Candidate C answers Question 1,2,4 and 5 correctly, he gets 26 marks.
Candidate D answers Question 1,3,4 and 5 correctly, he gets 27 marks.
Candidate E answers Question 2,3,4 and 5 correctly, he gets 28 marks.
Candidate F answers Question 1,2,3,4 and 5 correctly, find his total marks.
5) A factory produces several components, given that Worker A and Worker B can finish
the job individually in 18 days and 27 days respectively. If Worker A has done the jobs for x days firstly, then Worker B continues, they can finish it in 20 days. Find x.
6)Mary spent $100 to buy 100 writing tools, including fountain pens, ball-point pens and
pencils. It is given that the selling price of eacch fountain pen and ball-point pen are $4 and $3 respectively, while the selling price of pencil is $1 for 7 pencils, find the number of
fountain pen, ball-point pen and pencil that she bought.
更新1:
plz quick.I need it very much ,thx very much!!!
