<span>There is a decrease of 20% from ÂŁ800 to ÂŁ640.
A change from 800 to 640 represents a negative change (decrease) of -20% Using the formula :
Percent change = [(800 - 640) / 800] x 100 = -20 % (decrease)
800 is the old value and 640 is the new value. In this case we have a negative change (decrease) of -20 percent because the new value is smaller than the old value.</span>
Answer:
- The system of equations is x + y = 85 and 7/20x+2/5y=31
- To eliminate the x-variable from the equations, you can multiply the equation with the fractions by 20 and multiply the other equation by -7.
- B-She used 60 minutes for calling and 25 minutes for data.
Step-by-step explanation:
It is always a good idea to start by defining variables in such a problem. Here, we can let x represent the number of calling minutes, and y represent the number of data minutes. The the total number of minutes used is ...
x + y = 85
The total of charges is the sum of the products of charge per minute and minutes used:
7/20x + 2/5y = 31.00
We can eliminate the x-variable in these equations by multiplying the first by -7 and the second by 20, then adding the result.
-7(x +y) +20(7/20x +2/5y) = -7(85) +20(31)
-7x -7y +7x +8y = -595 +620 . . . . eliminate parentheses
y = 25 . . . . . . . . simplify
Then the value of x is
x = 85 -y = 85 -25
x = 60
Answer:
r= 3 h = 6 then use 3^2 + 6^2 = l^2
Step-by-step explanation:
Answer:
b
Step-by-step explanation:
b
