1)
Let x = the total amount of money they started off
Amount spent on gas = (1/4)x
They spent a fraction of what is left.
Amount spent on food & lodging = (1/4)[x - (1/4)x]
= (1/4)(3/4)x
= (3/16)x
They spend a fraction of what is left.
Amount spent on tourist attractions = (1/8)[(x - (1/4)x) - (3/16)x]
= (9/128)x
If we add up all the amounts they spent off, we get fraction of the money they spent.
(1/4)x + (3/16)x + (9/128)x = (65/128)x
The spent 65/128 of their entire money.
If they started with $840,
(65/128)(840) = 426.56
They spent $426.56
What they have left is
$840 - $426.56 = $413.44
2)
Convert minutes to seconds, since seconds is the dominant unit.
1 min = 60 sec
Kate's winning time = 60 sec + 27.38 sec = 87.38 sec
She finished 28/100 of a second ahead of Astrid. We can convert this fraction to a decimal for easy calculation.
28/100 = 0.28
She finished 0.28 of a second ahead of Astrid. So her time would be less than Astrid's since she finished first.
Astrid's time = Kate's time + 0.28 × (Kate's time)
= 87.38 + 0.28(87.38)
= 111.85 sec
3)
All of these place are from the same country.
Add the fractions that come from these specific areas,
2/5 + 3/10 + 1/10 =
4/10 + 3/10 + 1/10 =
8/10 =
4 / 5
This means that 1/5 of gold production comes from the rest of country.
Andrew M.
10/24/15