Express the scientific notation. 0.1588

1.588 x 10 and -1 at the top of the 10

Step-by-step explanation:

Move the decimal so there is one non-zero digit to the left of the decimal point. The number of decimal places you move will be the exponent on the

10

. If the decimal is being moved to the right, the exponent will be negative. If the decimal is being moved to the left, the exponent will be positive.

1) first ratio (words per min)

Data:
words=420 words
time=8 minutes

ratio₁= number of words/ time (minutes)
ratio₁=420 words/ 8 minutes=52.5 words/ minute.

Answer₁: the first ratio will be: r₁=52.5 words/ minute.      (52.5 words per minute)

2) Second ratio (time per words)
Data:
Time=8 minutes=8 minutes(60 seconds/1 minute)=480 seconds
number of words=420 words

Ratio₂=time/ words
Ratio₂=480 seconds/420 words≈1.14 seconds/word

Answer₂=    ratio₂=1.14 seconds/word  (1.14 seconds per word)

3)third ratio (words per hour)
Data:
time=8 minutes=8 minutes(1 hour/60 minutes)=2/15 hours≈0.133333... hours
number of words=420 words

ratio₃=number of words/ number of hours.
ratio₃=420 words/(2/15) hours=3150 words/hour.

Answer₃:    ratio₃=3150 words/hour  (3150 words per hour)