Puzzle 157
Can you find a five-digit number that...
...if you place a 9 at the beginning is four times larger than if you place a 9 at the end instead?
Puzzle Copyright © Kevin Stone
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Hint
What's a mathematical way to describe placing a 9 at the beginning?
Answer
23,076.
Reasoning
Placing the 9 at the beginning is equivalent to adding 900,000 (for example, 12,345 + 900,000 becomes 912,345).
Placing the 9 at the end is equivalent to multiplying by 10 and adding 9 (for example, 12,345 x 10 + 9 becomes 123,459).
Let's call the unknown number k, and we know that one of these numbers is 4 times the other, so:
k + 900,000 = 4 x (10k + 9)
k + 900,000 = 40k + 36
900,000 – 36 = 40k – k
899,964 = 39k
899,964 ÷ 39 = k
Therefore, k = 23,076.
Double-Checking
923,076 = 4 x 230,769.
Puzzle 158
Complete this grid of 4 four-letter words written horizontally.
Once complete, the first column of the grid forms a word, and the last column forms a word that is related to the first.
Puzzle Copyright © Kevin Stone
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Hint
The first word starts with H.
Answer
Hard and soft.
| H |
A |
T |
S |
| A |
L |
S |
O |
| R |
O |
O |
F |
| D |
E |
B |
T |
Puzzle 159
Two friends were driving from their home to Manchester, Alex drove the first 90 miles, and Billie took over for the remainder of the journey.
On the way back, Alex drove to begin with, and Billie took over for the last 100 miles.
Who drove the furthest?
Puzzle Copyright © Kevin Stone
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Hint
It doesn't matter how far it was to Manchester, so you can use any distance.
Answer
Billie.
Reasoning
If we call the one way distance T, we know that:
On the way there, Alex drove 90 miles, and Billie drove (T – 90) miles.
On the way back, Alex drove (T – 100) miles, and Billie drove 100 miles.
So, in total, both ways:
Alex drove 90 + (T – 100)
= T – 10
Billie drove (T – 90) + 100
= T + 10
Therefore, Billie drove 20 miles more than Alex.
Puzzle 160
What comes next in this sequence:
jnry fbrry mrch prl my jn {?}
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Share link: https://www.brainbashers.com/puzzle/zwyd
Hint
There are twelve items in the full sequence.
Answer
Jly.
From the months with their vowels removed. January, February, March, April, May, June, July.
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