speed of current is 1.5 mi/hr
Answer:
let the rate in still water be x and rate of the current be y.
speed down the river is:
speed=distance/time
speed=14/2=7 mi/h
speed up the river is:
speed=(14)/(3.5)=4 mi/hr
thus total speed downstream and upstream will be:
x+y=7...i
x-y=4.......ii
adding the above equations i and ii we get:
2x=11
x=5.5 mi/hr
thus
y=5-5.5=1.5 mi/r
thus the speed in still waters is 5.5 mi/hr
speed of current is 1.5 mi/hr
The complex conjugate of a + bi is a - bi
So, the complex conjugate of -8 + 12i is -8 - 12i.
The price:
- last year: $2.25
- this year: $.45
The decrease: $2.25 - $.45 = $1.80
2.25 : 1.80 = 100 : x
2.25 x = 180
x = 180 : 2.25
x = 80
Answer:
The percent of decrease is A ) 80%
Answer:

Try to solve the similtanious equation to find the first term and the common difference, then use that information to figure out the 80th term... Update me if you need further help ...
Answer:
28
Step-by-step explanation:
40% 6th graders of 70 total = 28 6th graders
40% 6th graders + 20% 7th graders = 60%
100% - 60% = 40% 8th graders
40% are 8th graders therefore the answer is 28