DAY 298

In a certain three-digit number, the digits add to 18. If you add 10 to the number, the sum of the digits is 1. What is the number?

Answer:

990

DAY 297

1/3 of the candles on your birthday cake are white, 1/6 are black, and 24 are yellow. How old are you?

Answer:

You're 48. (Half the candles are black and white.)

DAY 296

1/2 + 1/4 + 1/8 + 1/16 of a number = 480. What is the number?

Answer:

512

DAY 295

Using only 4's, can you add to 10,000?

Answer:

4,444 + 4,444 + 444 + 444 + 44 + 44 + 44 + 44 + 44 + 4 = 10,000

DAY 294

In a tug-of-war, 1 Boy = 1 Girl + 1 Dog. If it's 3 Boys against 2 Girls and 3 Dogs, who would win?

Answer:

The 3 Boys would win.

3B vs 2G + 3D

Since 1B = 1G + 1D

3G + 3D vs 2G + 3D

DAY 293

111,111,111 X 111,111,111 = 12,345,678,987,654,321

11 X 1.1 = 11 + 1.1

DAY 292

An electrician charges a basic fee plus an hourly rate. For 2 hours of work, he charged $74. For 4 hours of work, he charged $118. What is his basic fee and what is his hourly rate? This problem can be solved without algebra.

Answer:

His hourly rate is $22/hour and his basic fee is $30.

4 hours + fee - 2 hours + fee = 2 hours

$118 - $74 = $44 (2 hours of work without the fee)

$22 = hourly rate

$74 --- $44 = $30 (basic fee)

Using algebra:

Let x = fee

(74 - x) = 2 hours of work without fee

x + 2(74 - x) = $118

DAY 291

A $1 coin costs $.08 to make and will last 30 years. A $1 bill costs $.04 to make and will last 20 months. Over a 30-year period, how much more will it cost to replace the $1 bill than to produce the coin?

Answer:

$2.44

DAY 290

20 vehicles---cars and motorcycles---56 wheels. How many cars, how many motorcycles?

Answer:

8 cars and 12 motorcycles

Let n = cars ............ 4n + 2(20 - n) = 56

DAY 289

PIZZA PARTY

Fred's survey of 72 students found that 3 out of 8 preferred pepperoni pizza and 1 out of 8 preferred mushroom pizza. How many more students preferred pepperoni to mushroom?

Answer:

18 ........ 1/8 = 9/72 ......... 3/8 = 27/72 ........ 27 - 9 = 18