Dima called her friend to tell her that she saved 30% on her new skirt at a discount store. her friend told her that she could have gotten a better deal at a different store that was advertising a sale of 1/3 off all clothing. if the original price of dima’s skirt was $54, how much more could she have saved at the store her friend suggested?
a) $1.11
b) $1.80
c) $36.00
d) $37.80

Tom and maria typed in words in the ratio of 1 : 5 in 20 minutes. they typed 864 words altogether. find the number of words that each of them typed

Asmall (but heavy) particle placed in a glass of water will follow a zigzag motion because the particle will bounce off of the water molecules it meets. this is called brownian motion. a physicist simulates this on a computer, by varying the distance a particle can travel (called the mean free length), on average, before it collides with a water molecule and assigning the change in motion to be one of 8 directions, each with a similar probability. by running the simulated particle (with the same mean free length) many times she determines that it should take 15 seconds, on average, for the particle to fall to the bottom, with a standard deviation of 1.5 seconds. next she lets a real particle fall through a glass of water and finds that it took 18 seconds. what does she conclude, and why?

What is the first step of an indirect proof of a number that is divisible by two