Search found 3 matches
How many different positive integers are factors of 441?
A) 4
B) 6
C) 7
D) 9
E) 11
441=21^2
21=7*3
21^2=(7^2*3^2)
num of factors of a^n*b^m=(n+1)*(m+1)
num of factors of 7^2*7^3=(2+1)*(2+1)=3*3=9
- by vinaycfc
Sun Mar 09, 2014 6:57 pm- Forum: Problem Solving
- Topic: How many positive factors?
- Replies: 5
- Views: 9346
Of the 50 researchers in a workgroup, 40 percent will be assigned to team A and the remaining 60 percent to team B. However, 70 percent of the researchers prefer team A and 30 percent prefer team B. What is the lowest possible number of researchers who will NOT be assigned to the team they prefer? T...
- by vinaycfc
Sun Mar 09, 2014 6:48 pm- Forum: Problem Solving
- Topic: Grouping researchers
- Replies: 7
- Views: 6365
Total initial revenue is of last year =100$ Total initial revenue from car sales =75$ Total initial revenue from bus sales =25$ Total increase in car sales is 10%=>10% of 75=7.5 Total increase in bus sales =30%=>30% of 25=>25*3/10=7.5 total revenue this year due to car sales is 82.5$=>75+7.5 total r...
- by vinaycfc
Sun Mar 09, 2014 6:34 pm- Forum: Problem Solving
- Topic: total percent increase in sales
- Replies: 8
- Views: 2149