Puzzle 18
Are there more:
… square inches in a piece of carpet 15 yards by 5 yards
or
… feet in a 20-mile walk?
Puzzle Copyright © Kevin Stone
workings
hint
answer
print
www.brainbashers.com
/puzzle/zcag
share
Hint
There are 12 inches in a foot, and 1,760 yards in a mile.
Answer
Feet in a 20-mile walk.
Reasoning
There are 12 inches in a foot, 3 feet in a yard, and 1,760 yards in a mile:
square inches in a piece of carpet 15 yards by 5 yards
(15 x 3 x 12) x (5 x 3 x 12) = 97,200 square inches.
feet in a 20-mile walk
20 x 1760 x 3 = 105,600 feet.
Puzzle 19
After a day picking strawberries, I ended up with a full basket, which is always nice.
I ate 5, and then gave Alex half of the remaining.
I ate another 3, and then gave Billie one third of the remaining.
I ate another 6, and then gave Charlie two thirds of the remaining.
I now had 34 strawberries left. How many did I start with?
Puzzle Copyright © Kevin Stone
workings
hint
answer
print
www.brainbashers.com
/puzzle/zxgg
share
Hint
Try working backwards.
Answer
335 strawberries.
Reasoning
Working backwards …
I ended up with 34 strawberries, so I had 102 before giving Charlie two thirds.
I ate 6 myself, so I had 108 before I ate those.
I had 108 strawberries, so I had 162 before giving Billie one third.
I ate 3 myself, so I had 165 before I ate those.
I had 165 strawberries, so I had 330 before giving Alex one half.
Ate 5 myself, so I had 335 before I ate those.
Therefore, I started with 335 strawberries.
Double-Checking
I started with 335.
I ate 5, leaving 330.
I gave Alex half (165), leaving 165.
I ate 3, leaving 162.
I gave Billie one third (54), leaving 108.
I ate 6, leaving 102.
I gave Charlie two thirds (68), leaving 34.
Puzzle 20
If a bottle weighs eight ounces plus half a bottle …
… what is the weight of a bottle and a half?
Puzzle Copyright © Kevin Stone
workings
hint
answer
print
www.brainbashers.com
/puzzle/zpsd
share
Hint
Find the weight of the bottle first.
Answer
24 ounces.
The bottle weighs 16 ounces.
Reasoning
As a bottle (B) weighs eight ounces plus half a bottle, we can write this as:
B = 8 + 1/2 x B
1/2 x B = 8
B = 16
As the bottle weighs 16 ounces, a bottle and a half weighs 16 + 8 = 24 ounces.