Answers for Let’s Practice and Exit Ticket

Let’s Practice….

1.  Julie has $50, which is eight dollars more than twice what John has. How much does John have?

2x + 8 = 50

x = $21

2.  Carlotta spent $35 at the market. This was seven dollars less than three times what she spent at the bookstore; how much did she spend there?

3x − 7 = 35

x = $14

3.  Janet spent $100 on books. This was k dollars less than five times what she spent on lunch. How much did she spend on lunch?

5x − k = 100

x = 100 + k

5

4.  The sum of two numbers is 72, and one of them is five times the other; what are the two numbers?

x + 5x = 72.

x = 12. 5x = 60

5.  The sum of three consecutive numbers is 87; what are they?

3x + 3 = 87

x = 28 x + 1 = 29 x+ 2 = 30

6.  A group of 266 persons consists of men, women, and children. There are four times as many men as children, and twice as many women as children. How many of each are there?

Let x = The number of children

4x = The number of men

2x = The number of women

x + 4x + 2x = 266

x = 38. 4x = 152. 2x = 76.

7.  The sum of three consecutive integers that equal 39.

x + (x + 1) + (x + 2) = 39

x = 12, x + 1 = 13, x + 2 = 14

8.  The second angle of a triangle is 20° more than the first. The measure of the third angle is twice the measure of the first angle. Find all three angles.

x + (x + 20) + 2x = 180

x = 40°, x + 20 = 60°, 2x = 80°

Exit Ticket

If I invest $30,000 for one year. Part is invested at 2% interest per annum and the rest is invested at 3% per annum. I earn $800 after one year. How much did I invest at 2% and how much did I invest at 3%?

Step 1: Let x = amount invested at 2%

Step 2: $30,000 – x = amount invested at 3%

Step 3: I = prt

Step 4:[1]

x(.02)(1) + (30,000 – x)(.03)(1) = 800

.02x + 900 - .03x = 800

-.01x + 900 = 800

-.01x = -100

x = $10,000

Step 5:

x = $10,000 = amount invested at 2%

$30,000 – x = $30,000 - $10,000 = $20,000 = amount invested at 3%

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