Puzzle 81
Starting in the bottom left corner and moving either up or right, adding up the numbers along the way, what is the largest sum that can be made?
| 2 |
3 |
6 |
2 |
4 |
| 2 |
3 |
1 |
5 |
1 |
| 6 |
1 |
1 |
1 |
7 |
| 5 |
3 |
5 |
2 |
2 |
| 3 |
2 |
7 |
2 |
3 |
Note: this puzzle is not interactive, and the numbers cannot be clicked.
Puzzle Copyright © Kevin Stone
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Share link: https://www.brainbashers.com/puzzle/zxlf
Hint
The answer is not 31.
Answer
The largest sum that can be made is 34.
Puzzle 82
These words have had their vowels (AEIOU) removed, can you replace them to find some animals:
pnd
frrt
s ln
hdghg
chth
tdpl
ttr
plr br
lprd
grff
Puzzle Copyright © Kevin Stone
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Share link: https://www.brainbashers.com/puzzle/znct
Hint
The first word ends with the letter A.
Answers
pnd = panda
frrt = ferret
s ln = sea lion
hdghg = hedgehog
chth = cheetah
tdpl = tadpole
ttr = otter
plr br = polar bear
lprd = leopard
grff = giraffe
Puzzle 83
Last week I drove from Aardvark to Beeville.
On the first day, I travelled 1/3 of the starting distance.
On day two, I travelled 1/2 of the remaining distance.
On day three, I travelled 2/3 of the remaining distance.
At the end of day four, after travelling 3/4 of the remaining distance, I was still 5 miles away from Beeville.
How many miles had I travelled so far?
Puzzle Copyright © Kevin Stone
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Share link: https://www.brainbashers.com/puzzle/znkp
Hint
Try working backwards.
Answer
175 miles.
The total distance was 180 miles, but as I still had 5 miles to go, the required answer is 175 miles.
Reasoning
Let's try working backwards.
Day 4: I travelled 3/4, which means that the other 1/4 was 5 miles – so 20 miles were left at the start of day four.
Day 3: I travelled 2/3, which means that the other 1/3 was 20 miles – so 60 miles were left at the start of day three.
Day 2: I travelled 1/2, which means that the other 1/2 was 60 miles – so 120 miles were left at the start of day two.
Day 1: I travelled 1/3, which means that the other 2/3 was 120 miles – so 180 miles were ahead at the start of day one.
The full distance was therefore 180 miles, but we were asked how many miles I had travelled so far, and as I still had 5 to go the answer is 175 miles.
Double-Checking
Start distance: 180 miles.
Day 1: I travelled 1/3 of the distance (60 miles), leaving 120 miles.
Day 2: I travelled 1/2 of the distance (60 miles), leaving 60 miles.
Day 3: I travelled 2/3 of the distance (40 miles), leaving 20 miles.
Day 4: I travelled 3/4 of the distance (15 miles), leaving 5 miles.
Puzzle 84
Imagine a chessboard of size 20 x 20 instead of the normal 8 x 8.
How many squares, of any size, are there in total?
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Share link: https://www.brainbashers.com/puzzle/zoiv
Hint
How many 1 x 1 squares are there, how many 2 x 2, …?
Answer
2,870 squares.
Reasoning
We have squares sizes from 1 x 1 up to 20 x 20, and these are the counts:
1 x 1 = 400
2 x 2 = 361
3 x 3 = 324
4 x 4 = 289
5 x 5 = 256
6 x 6 = 225
7 x 7 = 196
8 x 8 = 169
9 x 9 = 144
10 x 10 = 121
11 x 11 = 100
12 x 12 = 81
13 x 13 = 64
14 x 14 = 49
15 x 15 = 36
16 x 16 = 25
17 x 17 = 16
18 x 18 = 9
19 x 19 = 4
20 x 20 = 1
Total = 400 + 361 + 324 + 289 + 256 + 225 + 196 + 169 + 144 + 121 + 100 + 81 + 64 + 49 + 36 + 25 + 16 + 9 + 4 + 1 = 2870.
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