Riddles
Using only addition, add eight 8s to get the number 1,000.
888 + 88 + 8 + 8 + 8 = 1,000
_ _ _
dog -- x
bat -- 2 bulls
act -- 1 bull, 2 cows
cat
Zara has a collection of 4 marbles: an Aggie, a Bumblebee, a Steelie, and a Tiger. She wants to display them in a row on a shelf, but does not want to put the Steelie and the Tiger next to one another. In how many ways can she do this?
12
Find the derivative of:
3x2-19+sinx+4
6x+cosx
In reply to an inquiry about the animals on his farm, the farmer says: “I only ever keep sheep, goats, and horses. In fact, at the moment they are all sheep bar three, all goats bar four, and all horses bar five.” How many does he have of each animal?
The farmer has 3 sheep, 2 goats, and 1 horse.
_ _ _ _
card -- 1 bull
lmao -- 2 cows
male -- 2 bulls
tank -- 1 bull, 1 cow
fast -- 2 bulls
moth -- 3 bulls
math
Suppose 15% of x equals 20% of y. What percentages of x is y?
75
Find the derivative of:
ex+e2x+e3x+e4x+sinx+cosx+tanx+cotx+secx+cscx
ex+2e2x+3e3x+4e4x+cosx-sinx+sec2x-csc2x+secxtanx-cscxcotx
What single digit appears most frequently between and including the numbers 1 and 1,000?
The most common digit is 1!
_ _ _ _ _
above -- 1 cow
plane -- 4 bulls
ticks -- 1 cow
wicks -- x
plant
Ralph went to the store and bought 12 pairs of socks for a total of $24. Some of the socks he bought cost $1 a pair, some of the socks he bought cost $3 a pair, and some of the socks he bought cost $4 a pair. If he bought at least one pair of each type, how many pairs of $1 socks did Ralph buy?
7
Find the average value of x2 from 0 to 2.
4/3
Three friends are on a road trip, and they rent a triple room for a night. When they get to the hotel, they pay the fee of $30 and go up to their room. The porter brings up their bags and refunds them $5 because the hotel is running a weeknight special. The three friends each keep one of the dollars and give the porter a $2 tip. Later, they sit down to work out their expenses for the weekend and find they have a problem.
They each paid $10 for the room and got $1 back each, making their contributions $9. Then they gave the porter a $2 tip. However, 9 times three is 27, plus two is $29. Where did the extra dollar go?
This one is a bit twisty, but what it boils down to is that the three friends’ math is wrong. They didn’t spend $29, they spent $27: $25 on the room, and $2 for the porter’s tip. The three remaining dollars were returned to them!
_ _ _ _
0 1 2 3 -- 1 bull, 1 cow
4 5 6 7 -- 1 cow
8 9 0 1 -- 2 cows
9 0 2 5 -- 2 cows
1 3 5 7 -- 1 cow
2 4 6 8 -- 1 bull
3 5 7 9 -- 1 bull, 1 cow
8 5 2 9 -- 1 bull
8 5 6 3 -- 1 cow
0 4 3 9
Three distinct integers are selected at random between 1 and 2016, inclusive. Which of the following is a correct statement about the probability p that the product of the three integers is odd?
p < 1/8
p = 1/8
1/8 < p < 1/3
p = 1/3
p > 1/3
p < 1/8
Find the limit of (sinx)/x as x --> 0.
1
Bonus +100 (either team): what is the name of the rule?
A small number of cards has been lost from a standard deck of cards. If I deal among four people, three cards remain. If I deal among three people, two remain and if I deal among five people, two cards remain. How many cards are there?
There are 47 cards.
_ _ _ _
0 1 2 3 -- 1 cow
4 5 6 7 -- 3 cows
8 9 0 1 -- x
2 4 5 6 -- 1 bull, 2 cows
2 5 6 7 -- 2 cows
3 7 5 4 -- 3 bulls
3 4 5 7 -- 2 bulls, 1 cow
3 6 5 4
How many ways are there to write 2016 as the sum of twos and threes, ignoring order? (For example, 1008*2 + 0*3 and 402*2 + 404*3 are two such ways.)
337
Find the integral of (cosx)/sqrt(sinx+2023) dx
2sqrt(sinx+2023)+c
if +c forgotten, instead of -500, it is -1000