Coolio

22 Questions
5 Answers

0

655

1

+87

Fraction work

Lizzie can paint a fence in 6 hours, while it takes Alex 8 hours to paint the same fence. How long in hours would it take them to paint the fence if they worked together? Express your answer as a common fraction.

Coolio Jun 8, 2020

-1

680

1

+87

5 digits

How many five-digit numbers beginning in a 6 have exactly one pair of identical digits?

Coolio May 31, 2020

-1

779

1

+87

Marbles

A bag contains ten identical blue marbles and ten identical green marbles. In how many distinguishable ways can five of these marbles be put in a row if there are at least two blue marbles in the row and every blue marble is next to at least one other blue read more ..

Coolio May 31, 2020

0

1966

2

+87

Cube

The faces of a cube are to be numbered with integers 1 through 6 in such a way that consecutive numbers are always on adjacent faces (not opposite ones). The face numbered 1 is on top and the face numbered 2 is toward the front. In how many different ways read more ..

Coolio May 31, 2020

0

2229

2

+87

How many even, three-digit positive integers have the property that two of the digits are equal, but not all three are equal?

How many even, three-digit positive integers have the property that two of the digits are equal, but not all three are equal?

Coolio May 31, 2020

-1

639

1

+87

Clothing Casework

Dustin has five hats, five shirts, five pairs of pants, and five pairs of shoes; he has one of each in blue, green, gray, silver, and gold (his five favorite colors). Dustin is picky about what he wears: he insists on his shoes being the same color as at read more ..

Coolio May 31, 2020

0

681

1

+87

Casework with a deck of cards

A standard deck of playing cards has cards divided into four suits (clubs, diamonds, hearts, spades). Each suit consists of nine "number cards," each containing a different number from to , and four "face cards" that include read more ..

Coolio May 31, 2020

-1

1193

2

+87

How many positive three-digit integers strictly greater than 500 have at least two digits that are the same?

How many positive three-digit integers strictly greater than 500 have at least two digits that are the same?

Coolio May 31, 2020

-1

675

1

+87

Football Casework

In American football, a touchdown scores 7 points, a field goal scores 3 points, and a safety scores 2 points. If a team scored a total of 24 points, how many combinations of plays is possible? The order of the plays does not matter, so touchdown and field read more ..

Coolio May 31, 2020

-1

731

1

+87

Casework

Kraken's passcode is at most 3 letters long. We know it only contains capital letters, and that it definitely doesn't include Q. How different many passcodes can Kraken have?
Assume Kraken's passcode is at least 1 letter long.

Coolio May 31, 2020

0

622

1

+87

Help

In the expansion of (1+x)^n there exist three consecutive coefficients a,b,c that satisfies a:b:c=1:7:35 Find the positive integer n

Coolio Apr 29, 2020

0

749

2

+87

Simplify

Simplify C(n,k)/C(n,k-1)

Coolio Apr 29, 2020

+87

+4

Actually, I got it. The right answer was 10.

CoolioJun 1, 2020

+87

0

Thank you!

CoolioJun 1, 2020

+87

0

No, but it's fine I got it. The answer was 139, you were so close. Thank you though!

CoolioMay 31, 2020

+87

+1

TYSM!!

CoolioApr 29, 2020

+87

-1

Since there 100 numbers in total and 10 numbers that are "successful", 10/100=1/10 is the answer.

CoolioApr 1, 2020