A 3-digit number ABC satisfies A+C=2B. How many possible numbers are there?
A 3-digit number ABC satisfies:
A<B<C
The digits are consecutive integers.
How many numbers satisfy these conditions?
Ten identical tiles are placed into up to four labeled piles (some piles may be empty). How many distributions produce exactly two nonempty piles?
For a 4-digit number ABCD, A = D, B = C, and A + B is odd. A cannot be 0. How many numbers meet these criteria?
A 4-digit number ABCD satisfies A = D and B+C=9. How many such numbers exist?
A 3-letter code uses the letters A, B, C, and D. How many codes have at least one A?
You roll two dice. In how many outcomes does the product of the dice equal a multiple of 6?
A number is formed using digits 1, 2, 3, and 4 (each used once). How many 4-digit numbers are odd and have digits increasing from left to right in at least one position? Ex: 4231(3 is larger than 2).
Three different numbers between 1 and 9 are chosen so that their sum is odd. How many possible sets are there?
How many rectangles are in a 2×3 grid of squares?