First, you drive 123km per day, and they ask for in a week.
There are 7 days in a week, we have to multiply 123 by 7, which equals 861.
=km per week 861
Now, we need to find out how much cost the gas. Gas cost 1.10 euros per-liter, and this problem wants us to assume that 1euro = 1.26 dollars.
So, we divide 1.10 by 1.26 which is 0.87.
=gas cost 0.87 per liter.
Next, this person goes 31.0 mi/gal per stop.
To get the answer we need to divide 861 the full distance in a week and divide it by how many stops nee to be made which is each 31 mi/gal.
So, 861/31 = 27.77 and now we times 0.87 by 27.77 to get gas cost.
=24.16
A² = c² - b²
a² = 21² - 13 ²
a² = 441 - 169
a² = 272
a = √272 = 16.49242 ≈ 16.49
Answer : D ) 16.49
The answer is 81 < < 105
Explanation: Since the car gets 27 mpg in the city and gets 35 mpg on the highway, you can set it up in the inequality 27 < < 35 and this represents the range a car can drive for 1 gallon, so to find the range for 3 gallons, you multiply this inequality by 3.
27(3)<<35(3)
27(3)=81
35(3)=105
Then you can insert the numbers into the inequality to get 81<<105.
If something costs $28<span> and is on sale for </span>18<span>% off, then how much would it cost?
</span>
5.04 U.S. dollars
4, 5, and 7 are mutually coprime, so you can use the Chinese remainder theorem right away.
We construct a number 
such that taking it mod 4, 5, and 7 leaves the desired remainders:
- Taken mod 4, the last two terms vanish and we have
so we multiply the first term by 3.
- Taken mod 5, the first and last terms vanish and we have
so we multiply the second term by 2.
- Taken mod 7, the first two terms vanish and we have
so we multiply the last term by 7.
Now,
By the CRT, the system of congruences has a general solution
or all integers 
, 
, the least (and positive) of which is 27.
