Posted by Chris on Thursday, February 3, 2011 at 9:26am.
You question is not clear.
Are all these age problems based on the 10 year old, 55 year old and 75 year old or are these separate problems?
Are these ages three different people?
For example, "at my age of 55, in years, how old was the older person of 75 when I was born?"
Based on this wording, my answer to you would be,
75 - 55 = 20
The older person was 20 when you were born 55 years ago.
How old in years each of us will be, when our ages add up to 150 years old?
x = 10yo
x + 45 = 55yo
x + 65 = 75yo
x + x + 45 + x + 65 = 150
3x + 110 = 150
3x = 40
x = 13.33
x = 13.33 = age of 10yo
x + 45 = 58.33 = age of 45yo
x + 65 = 78.33 = age of 75yo
In years, how old were you when the youngest person was born?
55 - 10 = 45
Is this what you are looking for?
Refer back to Week One Discussion and use the names and ages of yourself and the other two people you selected. Make sure one is older than you and one is younger than you.
In years, how old was the older person when you were born?
Write an equation that models how old in years each of you will be, when your ages add up to 150 years old. For example, if x = your age and the eldest person was a year older than you, you would write their age as x + 1. Then the equation would be: x + (x+1) = 150.
Explain the reasoning which helped you develop your equation.
Solve for your future ages. Are your answers reasonable, do they add up to 150?
In years, how old were you when the youngest person was born?
At some point during the lives of you and the youngest person, your age will be three times his/her age at that moment. Write an equation which models how old in years each of you will be when you are three times as old as the younger person.
Explain the reasoning which helped you develop your equation.
Solve the equation for your ages when you are three times as old as the youngest person. Are your answers reasonable?
Respond to at least two of your classmatesâ€™ postings. Check their equations and investigate for mathematical errors. Help with a constructive critique.