f = t = n five ten and twenty
5n + 10n + 20n = 560
35n = 560
n = twenty dollar coins = 16
x + 7 = 2(3x - 4) Remove the brackets
x + 7 = 2*3x - 4*2
x + 7 = 6x - 8 Subtract 7 from both sides.
x + 7 - 7 = 6x - 8 - 7
x = 6x - 15 Subtract 6x from both sides
x - 6x = - 15
-5x = - 15 Divide by -5
-5x/-5 = -15/-5
x = 3
To find how long it would take him, one has to divide 400 by 160 and then multiply 5 by what that number is. You multiply 5 by the quotient because that is the number that would make it proportional. 400/160 x 5 is 12.5, meaning that the answer is 12.5 minutes, or A.
Answer:
There are 8 numbers.
4 of the numbers are even ( 2, 4, 6, 8)
The probability is the number of even numbers over the total numbers:
4/8 which reduces to 1/2.
The answer is 1/2