Sam and Dean are brothers. Their ages now add up to the age of their sister. In ten years, Dean's age will be the sum of their ages today. How old are each of them?

Sam is  yeas old, and Dean is (x - 10) year's old, where 'x' is the age of their sister

Step-by-step explanation:

The relationship between the ages of the brothers are;

Sam's age + Dean's age = Their sister's age

Dean's age + 10 = Dean's age + Sam's age

Therefore, we have;

Sam's age = Dean's age + 10 - Dean's age = 10

Sam's age = 10 years

Let 'x' represent their sisters age, we get;

Sam's age + Dean's age = x

10 + Dean's age = x

Dean's age (in variable form) = x - 10

answer set (b) 0.5, 3/4 80% is in order from least to greatest.  

step-by-step explanation:

in order to compare rational numbers to each other, it is much easier if they are in the same form.   typically, the best form in which to evaluate rational numbers is in decimals.   in order to convert a percent to a decimal, you would divide the given percentage by 100.   you can also accomplish the conversion by moving the decimal point over two places to the left.   for example, the decimal value of 80% is 80/100, or 0.8.   in order to convert a fraction to a decimal, you need to divide the numerator by the denominator.   for example, 3/4 is 0.75.   so, for choice (b) 0.5 3/4 (0.75), 80% (0.8) is the only choice in which the numbers are in order from least to greatest.