Answer:
3howers
Step-by-step explanation:
Step-by-step exaplanation
Answer:
a) 91 1/6 gallons
b) 2502 miles
Step-by-step explanation:
You are given a number of miles and a number of gallons for the car. The ratio of these numbers is ...
(261 mi)/(14.5 gal) = 18 mi/gal
We presume this value is constant for this car. Then the questions can be answered by forming and solving a proportion:
a) 1641 miles/(gallons) = 18 mi/(1 gal)
Multiplying by gallons and dividing by 18 mi/gal, we get
1641/18 gal = (gallons) = 91 1/6 gal
It will take 91 1/6 gallons of gasoline for Mary to drive to her friend's house.
___
b) Same deal, but the miles are unknown.
(miles)/(139 gal) = (18 mi)/(1 gal)
Multiplying by 139 gal gives ...
(18 mi)·139 = (miles) = 2502 mi
139 gallons of gasoline will let Mary drive 2502 miles.
Since you need a little bit of trigonometry to solve this problem,
I'm pretty sure you've had a little bit of trigonometry in class before
you were assigned to solve this problem.
-- The shaded triangle comes from taking the equilateral triangle and
either folding it in half or cutting it in half.
-- The base that the new triangle is standing on is 1/2 the base of the
equilateral triangle, so it's 7 cm long.
-- The acute angle at the right end of the base is the same as it was in
the equilateral triangle . . . 60 degrees.
-- The tangent of 60 degrees is (opposite side)/(adjacent side) = x / 7 cm
tan(60) = x/7
-- Multiply each side of this little equation by 7 : 7 tan(60) = x
If you don't have the tangent of 60 degrees in your pocket, you can
find it with your calculator. Multiply it by 7, and Shazam, you know 'x' .
