First, convert the distance of a typical marathon to kilometers.
1 mi = 1.609 km
26.2 miles = 42.165 km
Divide this distance by Allan's average speed to get his average time.
42.165 km / 12 km/hr = 3.514 hours
So 16=heads
18=tails
after you add some tails
18+x
ratio of heads to tails is 1:1.5
heads=16, didn't change
tails=18+x
so
1:1.5=16:18+x
fractionify
1/1.5=16/(18+x)
1/1.5=2/3
2/3=16/(18+x)
mutiply both sides by (3)(18+x)
2(18+x)=3(16)
36+2x=48
subtract 36 from both sides
2x=12
divide 2
x=6
6 tails added
total=heads+tails
heads=16
tails=18+6=24
total=16+24
total=40
6 tails added
40 total coins
Answer:
x^2+x+1
Step-by-step explanation:
(3x^2+4x−1)+(−2x^2−3x+2)
Combine like terms
3x^2-2x^2+4x-3x-1+2
x^2+x+1