40/60=60/x...forty miles in sixty minutes is equal to 60 miles in 40 minutes.....40x=3600....x=90..90 minutes
Yes, to convert the ratio into the percentage, divide, the multiply the result by 100, and there is your answer !!.
Slope is given by the expression:

We can equal both slopes of mAC and mCE

Answer is B.
Log₄20-log₄ 45+log₄144=
log₄(20/45)+log₄144= (log_a b- log_a c=log_a (b/c) )
log₄[(20*144)/45]= (log_a b +log_a c=log_a (b*c) )
log₄(2880/45)=
log₄(64)=n ⇔ 4^n=64 (log_a x=n ⇔ a^n=x)
4^n=4³ ⇒n=3 (64=4*4*4=4³)
Answer: log₄20-log₄ 45+log₄144=3