Each month, a new set of puzzles will be posted. Come back next month for the solutions and a new set of puzzles, or subscribe to have them sent directly to you.



Feedback
There are more than one way of doing these puzzles and may well be more than one answer. Please let me and others know what alternatives you find by commenting below. We also welcome general comments on the subject and any feedback you'd like to give.
If you have a question that needs a response from me or you would like to contact me privately, please use the contact form.
Get more puzzles!
If you've enjoyed doing the puzzles, consider ordering the books;
 Book One  150+ of the best puzzles
 Book Two  200+ with new originals and more of your favourites
Both in a handy pocket sized format. Click here for full details.
Last month's solutions
1. A summer camp counsellor wants to find a length, x, in feet, across the lake as represented in the sketch below. The lengths represented by AB, EB, BD and CD on the sketch were determined to be 1800 feet, 1400 feet, 700 feet, and 800 feet, respectively. Segments AC and DE intersect at B, and angles AEB and CDB have the same measure. What is the value of x? Solution: 
Since the angles AEB and BDC have the same measure as well as angles ABE and CBD, triangles (two pairs of congruent corresponding angles). Since the triangles EAB DCB are similar, their corresponding sides are in the same proportion; thus CD/x = BD/EB. Substituting the given values, then CD/x = BD/EB becomes 800/x = 700/1400. Therefore, x = (800 * 1400) / 700 = 1600 feet. 
2. A food truck sells salads for $6.50 each and drinks for $2.00 each. The food truck’s revenue from selling a total of 209 salads and drinks in one day was $836.50. How many salads were sold that day? Solution: Let x = total number of salads sold and y = total number of drinks sold. x + y = 209, y = 209 – x, and 3. How many litres of a 25% saline solution must be added to 3 litres of a 10% saline solution to obtain a 15% saline solution? Solution: Let x = the amount, in litres, of a 25% saline solution to be added. Then 3(0.10) + 0.25x = 0.15(x + 3), then 0.25x – 0.15x = 0.45 – 0.30 
Excellent, thanks Mr. Burgin! I soooo look forward to trying to conquer March ’21 puzzles!