After going a month without a winner, there was one in Mr. Math Puzzler’s May competition

Eleven-year-old Zachary Bian from Grace Christian Academy got all six May Puzzlers correct. There had been no winners in the April contest.

Mr. Math Puzzler is Wayne Hesse from Green Park Lutheran School in south St. Louis County. He said he had eased up a bit on the May questions, after there were no winners in April.

But, he must not have eased up too much since Zachary was the only winner in May.

In addition to having his name published in this article, Zachary wins a $10 Borders book certificate. Young Saint Louis.com awards certificates to up to three winners. Of course, since there’s only one winner, Zachary will get the only certificate.

After spring breaks in April, there were more entries in the May contest. But, there’s lots more room for entrants in the June Puzzler contest.

Why don’t you tell some of your friends about Mr. Math Puzzler. Also, you could ask your math teacher if she would give some “extra credit” if you and other classmates enter the contest.

As we’ve said in the past, first time entrants don’t win very often. It helps if you practice some before sending in your June entry form.

The Math Puzzler contest has been on YSL.com since September, 2001.

That’s about 200 Puzzlers that have run in previous issues. Also, for all of those past editions, there has been an answer story the next month.

By going to the Past Stories tab at the top of the Home Page, you can get access to all past Puzzlers. Pick a sampling of months, look at the questions and then see how Mr. Math Puzzler figures out the answers.

A review of all those Math Puzzlers also may help you understand more math principles.

After reviewing previous questions and answers, come back here and enter the June test.

The May Math Puzzlers answers:

1. What day would yesterday be if Wednesday was five days before the day after tomorrow?

Answer: Friday

The explanation: This answer is best found by using a linear chart:

 

2. Susie is throwing darts at a dart board shown. Assuming that all her darts hit the board, how many darts will she need to throw to get 100 points exactly?

Answer: Six

The explanation: There are several possible combinations: (1) 15, 15, 16, 16, 19, 19; (2) 15, 15, 16, 17, 18, 19; (3) 15, 15, 17, 17, 18, 18. But, all of them use six darts to get to 100.

 

3. A car-rental agency charges $37.50 per day and 23 cents-per-mile to rent a car. How many miles (whole miles) can be driven in a day before the charge reaches $100?

Answer: 271

The explanation: This answer is best arrived at with a formula:

     37.5 + .23m < 100
    -37.5          -37.5
    -----          -----
                         .23m <  62.5

 

    .23m ÷ .23 < 62.5 ÷ .23

    m < 271.73913
    Rounded to m = 271

 

4. How many terms (or numbers) are in the sequence that follows?

3, 7, 11............439

Answer: 110

The explanation: The gap between the numbers in the sequence is four. Therefore, there should be 110 terms (or numbers) since 439 divided by four (with 1 added) is 110.

 

5. Find a number X that makes this statement true?

(x ÷ 3²) - 4 + (3 times 2³) = 36

Answer: 144

The explanation: Here’s how the completed formula answer looks:

(x ÷ 3²) - 4 + (3 times 2³) = 36

(x ÷ 9) - 4 + 24 = 36

(x ÷ 9) - 4 + 24 -20 = 36 - 20

9(x ÷ 9) = 9(16)

x = 144

 

6. What is the sum of ALL the prime factors of 1,260?

Answer: 22

The explanation: You need to divide 1,260 by prime numbers to get to 1.

1260 ÷ 2 = 630
630 ÷ 2 = 315
315 ÷ 3 = 105
105 ÷ 3 = 35
35 ÷ 5 = 7

7 + 5 + 3 + 3 + 2 + 2 = 22