Q: Find the three digit number that when you multiply it by two, it is one more than the reverse of the original number.
For example, 102 doubled is 204 which is 3 more than the reverse (201).
A: 397
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October 2016 Brain Teaser Solution
Q: MAD + AS + A = BULL
Each letter stands for a number 0 -9 but not all digits will be used.
Each letter stands for a number 0 -9 but not all digits will be used.
If D = 3 and L = 7, find the value of the other letters
A:
983 + 86 + 8 = 1077
writing it vertically helps a lot
The B has to be a 1 as the total would be over 1000 and the M has to be a 9 as we are only adding a two digit and 1 digit number and getting over 1000
the last column must be adding up to 17 rather than 7 (otherwise S + A would be 4 and would be 1 and 3 but 3 is already used)
so S + A = 14 and since there will be a carry the next column over A + A + 1 will equal 17
so A = 8 and therefore A = 6
Get the Math and Points: Aug 2016 CC Alg I Regents #13
So which one is NOT true??
(1) At o seconds, height was 180 so this is ok
(2) The highest height was 324 ft which happened at 3 seconds
(3) Um, at 7 seconds, it is still 68 feet above the ground
(4) From 2 to 4 seconds, the height is in the 300s
September 2016 Brain Teaser Solution
Q: How many integers between 1000 and 9999 have four distinct digits?
A: 1234 would be an example of a 4 digit number with distinct digits (no repeats!)
You have 9 choices for the first 1-9 (no leading zero)
You have 9 choices for the second because there are 8 left plus the zero
You have 8 choices for the third and
A: 1234 would be an example of a 4 digit number with distinct digits (no repeats!)
You have 9 choices for the first 1-9 (no leading zero)
You have 9 choices for the second because there are 8 left plus the zero
You have 8 choices for the third and
7 choices for the fourth digit
so 9 x 9 x 8 x 7 = 4536
Get the Math and Points: Aug 2016 CC Alg I #10
Each number in the sequence is 4 less than the number before so the rate of change is -4.
Putting that Y= – 4x – 2 into Y= gives this xy table where you can see the pattern and voila the 6th number is indeed -26!
