Help w/ Bernie weighs 90 pounds plus half his own weight....

bibi

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Bernie weighs 90 pounds plus half his own weight. What does Bernie weigh?
 
Bernie weighs 90 pounds plus half his own weight
let w = bernie's weight ...

w = 90 + w/2

solve for w
 
When doing simpler word problems, you should take them word by word and try to make them into an equation like skeeter has done. I would start with "Bernie weighs" because the question you're asked is "what does Bernie weigh?", so in a sense, what the sentence is about to tell you is your answer, right?

"Bernie weighs" = the rest of your equation

Next, the sentence tells you a number and a fraction - numbers are good. Lets take "90 pounds plus" first. Now you have:

"Bernie weighs" = "90 pounds plus"

or

"Bernie weighs" = 90 lbs. + >>>>>>>>>>>>>>>>>>> Correct?

Alright, now just finish off that blank. All you have left is "half his own weight". Whose weight? Bernie's, right? Wait, we know what "Bernie weighs"! So they're just asking for half of that. In other words:

"half his own weight" = "Bernie weighs" divided by 2

or

"half his own weigh" = "Bernie weighs"/2


Almost done now. Putting it all together, you get:

"Bernie weighs 90 pounds plus half his own weight"

or

"Bernie weighs" = 90 lbs. + ( "Bernie weighs"/2 )

You can even simplify that equation to what skeeter has by substituting "Bernie weighs" with a single letter (also known as a variable) like w, giving you:

w = 90 lbs. + (w/2)
w = 90 + w/2

So you see, they basically gave you the answer before they even asked the question! Solving for w, you get:

w = 90 + w/2
2w = 180 + w
2w - w = 180
w = 180

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