During each minute of a comedy show, carlin laughs 555 times. carlin watches 333 comedy shows every day, and each show is 404040 minutes long.
how many times does carlin laugh every day due to the comedy shows?
choose 1

the answer is b.)

< 1=< 2

the monthly balance will be $75,000

ending amount = beginning amount / (2^n)

where "n" = number of half-lives (or elapsed time / half-life)

ending amount = 50 mg / (2 ^10 / 5.3)

ending amount = 50 mg / (2 ^ 1.8867924528)

ending amount = 50 m / 3.6981210597

ending amount = 13.5203794557 mg

or about 13.5 mg remain

source:  

-1/4 > -1 2/3. -1/4 is greater than -1 2/3 because it is closer to 0 on the number line.