Algebra Pinkston

SAT Question What is the greatest possible sum of three consecutive even integers whose product is zero? A.-6 B.-3 C.0 D.3 E.6 Zero has to be one of the numbers, so the possibilities are: -4, -2, 0 -2, 0, 2 0, 2, 4 The one that gives the greatest sum is the last one: sum is 6.

Solving Word Problems In Algebra County

Write H eading Write E quation S olve Equation Write S olution asked for

On Wednesday, Harry picked 3 times as many quarts of berries as on Tuesday. On Thursday, he picked 5 times as many quarts as on Tuesday. In all he picked 153 quarts. Find the number he picked each day. The heading defines the variables needed to solve the problem. x is the variable we know the least about.

On Wednesday, Harry picked 3 times as many quarts of berries as on Tuesday. On Thursday, he picked 5 times as many quarts as on Tuesday. In all he picked 153 quarts. Find the number he picked each day. For this problem, we need to make variables for: Tuesday Wednesday Thursday Which one do we know the least about?

On Wednesday, Harry picked 3 times as many quarts of berries as on Tuesday. On Thursday, he picked 5 times as many quarts as on Tuesday. In all he picked 153 quarts. Find the number he picked each day. “In all” means add up all the variables for each day.

Now, go back to the heading to write all the solutions asked for.

On Wednesday, Harry picked 3 times as many quarts of berries as on Tuesday. On Thursday, he picked 5 times as many quarts as on Tuesday. In all he picked 153 quarts. Find the number he picked each day. For this problem, we need to make variables for: Tuesday Wednesday Thursday

Tuesday Wednesday Thursday We can check it by adding the three answers together to see if we get 153.

Example 2 The time that a traffic light remains yellow is 1 second more than 0.05 times the speed limit. What is the yellow time for a traffic light on a street with a speed limit of 30 mi/h? Heading: x = yellow time y = speed limit Equation: x = 1+.05y (Substitute 30 for y) x =1+.05(30)

Solve: x =1+.05(30) x = 2.5 Write solution: 2.5 sec.

Example 3 It has been found that the world record for the men’s 10,000 meter run has been decreasing steadily since The record is approx minutes minus.05 times the number of years since Assume the record continues to decrease in this way. Predict what it will be in Heading: x = world record y = years since 1950 Equation: x = y

Solve: x = y Substitute 60 for y x = Write solution: min.

To find the percent of increase or decrease: Amount of increase or decrease Original number Example 3: 16/p. 33. In 1995 the average American ate 48.8 lb of chicken. This was 6.3 lb more than the average in What was the percent of increase in chicken consumption from 1990 to 1995?

Amount of increase or decrease Original number = 48.8 – % In 1990In Increase ??6.3

SAT Question If x and y are negative integers, which of the following must be positive? A.x + y B.x – y C.y – x D.– (x – y) E.– (x + y) A. (-) + (-) is negative B. (-) – (-) could be negative or positive C. Same as above D. - [(-) - (-)] could be either E. - [(-) + (-)] is definitely positive !

Classwork: 2, 8, 12, 16 / 33

Get ready for a “Small Quiz” to be written on your grade sheet.

Solve and write answer in set notation: Quiz. Copy the problems and write the answer. Put your grade paper on the front of your row, quiz side down.

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