To roast a chicken, it should be cooked in the oven at 325 degrees Fahrenheit for 20 minutes per pound plus an additional 20 minutes. If a chicken takes one and a half hours to roast at 325 degrees Fahrenheit, write an equation that you could use to find 𝑤, the weight of the chicken.
One and a half hours is equal to 60 minutes plus 30 minutes, as there are 60 minutes in one hour. This means that the total cooking time was 90 minutes. We were told in the question to let 𝑤 be the weight of the chicken. It takes 20 minutes to cook per pound. This is equal to 20𝑤. The chicken also needs to be cooked for an additional 20 minutes. Therefore, an expression for the total cooking time is 20𝑤 plus 20. This particular chicken took 90 minutes to cook. Therefore, the equation is 20𝑤 plus 20 is equal to 90.
We could then use this equation to work out the weight of the chicken. Subtracting 20 from both sides of the equation gives us 20𝑤 is equal to 70. Dividing both sides of this equation by 20 gives us 𝑤 is equal to 70 divided by 20. We can simplify this fraction by dividing the numerator and denominator by 10. This leaves us 𝑤 is equal to seven divided by two. Seven divided by two is equal to 3.5. Therefore, the weight of the chicken is 3.5 pounds.