







Surrounding a pipe with concrete 
20130611 

From jeanne: I need 2 inches of cement around a 20 inch pipe that is 20 feet long. Thank you. Answered by Penny Nom. 





The surface area of a pyramid 
20130611 

From Sam: A right rectangular pyramid has a rectangular base measuring 18 cm by 32 cm. The height of the pyramid is 12 cm. What is the surface area? Answered by Penny Nom. 





Two numbers whose difference is 16 
20130608 

From Johan: Two numbers whose difference is 16 and whose sum is 120 Answered by Penny Nom. 





How much does Sara get to take home 
20130605 

From Jessica: Sara gets paid $15.00 an hour. She worked 80 hours during the pay period. If 28% of what she earned is deducted for taxes, how much does Sara get to take home? Answered by Penny Nom. 





Percent change in sales 
20130604 

From Sui: Hi,
I would like to ask your favor for reviewing the following percent change in sales calculation, did I do it right? I am surprise/wondering with the big amount of the percentage result. Your assistance and guidance would be highly appreciate.
Sales for month of August 2000: 5,198,750 IDR
Sales for month of October 2000: 62,291,700 IDR
Difference = 62,291,700 IDR  5,198,750 IDR = 57,092,950 IDR
Percentage change = 57,092,950 IDR : 5,198,750 IDR = 10.98 X 100 = 1,098%
Sales for month of February 2008: 1,664,800 IDR
Sales for month of August 2008: 161,715,307 IDR
Difference = 161,715,307 IDR  1,664,800 IDR = 160,050,507 IDR
Percentage change = 160,050,507 : 1,664,800 = 96.14 X 100 = 9,614%
Thanking you,
Sui Answered by Penny Nom. 





A kennel for a beagle 
20130603 

From david: Hi, I'm building some beagle kennels and I am in need of help with an angle problem. I need to place a roof on my kennel with a drop of 2inches across 3ft 10inches. the posts on the right side will be 5ft and the post on the left will be 4ft 10in. the posts are 4x4 and the space to be covered is 3ft 10in from the outside of the 4x4. Please help, thanks. Answered by Penny Nom. 





A pump is operating at 70% 
20130603 

From Abdel: Hi I was wondering if you could help me out on a question I recently got on an aptitude test.
A pump operates at 70% if it is pumping out 4500 gallons then how much will it pump out at 85%? Answered by Penny Nom. 





Four circles 
20130529 

From varsha: four circular cardboard pieces each of radius 7cm are placed in such a way that each piece touches two other pieces. find the area enclosed by the four pieces. Answered by Penny Nom. 





21 golfers 
20130527 

From Linda: A database search for a question on how to schedule 20 golfers in groups of 4 was very helpful ( Mona's answer referred to by C. Fisher 932008) I'm very glad I found this sight.
Our problem is we will have 21 golfers in the second half of the season. Is it possible to figure out that schedule? I assume we will have to include byes, but I'm not sure how to go about doing that.
Thank you. Answered by Victoria West. 





Simson line 
20130523 

From Nazrul: From any point p lying on the circumcircle of the triangle perpendiculars
PD , PE are drawn on BC,CA respectively. The line segment ED intersects at
the point 0 ; prove that PO ⊥ AB ( PO is perpendicular to AB ). Answered by Chris Fisher. 





Two overlapping circles 
20130522 

From Alexandra: There are two overlapping circles. The two nonoverlapping regions have areas A and B.
As the area of overlap changes, the values of A and B also change.
Prove that no matter how big and small the overlap is, the difference between
A and B is always the same. Answered by Penny Nom. 





How many acres does a 4.5 mi strip 52 inches wide make? 
20130521 

From Aaron: How many acres does a 4.5 mi strip 52 inches wide make? Answered by Lorraine Dame. 





The dimensions of my property 
20130521 

From Mr.: My property is 196 feet wide an I own 2 1/2 acres how many feet in depth is it Answered by Lorraine Dame. 





How many acres are in 212 ft 1 mile long? 
20130520 

From Connie: How many acres are in 212 ft 1 mile long? Answered by Penny Nom. 





GCD 
20130520 

From Julia: Prove that if a and b are coprime integers, the greatest common divisor of a + b and a  b is either 1 or 2. Answered by Penny Nom. 

