The sum of two numbers is 10. The larger number is 4 more than the smaller number. What is the value of the larger number?

The sum between a negative number and 30 is 9 . What is the number?

The sum of two numbers is 6. Find the value of the smaller number if the larger number is twice the smaller number. 

Beth is twice as old as Lean. After 5 years, Beth is 17 years old, what is Lean’s present age?

How many liters of a 10% sugar solution must be mixed with 5 liters of a 30% sugar solution to make a 20% sugar solution?

Jerry is twice as old as Ben. If Jerry is 20 years old right now, what is Ben’s present age?

Jenny needs a 10% saline solution. How many grams of pure water is to be added to 30 grams 20% saline solution to produce this mixture?

Grace is 4 years older than Faith. If Grace is 10 years old at present, what will be Grace's age after 5 years?

How many liters of 40% alcohol solution is produced if a 30% solution is added to 20 liters of a 50% alcohol solution?

Beth is twice as old as Lean. After 5 years, Beth is 17 years old, what is Lean’s age after 5 years?