1 / 15

BELLRINGER (DAY 79)

BELLRINGER (DAY 79). Workbook page 105-106 x = 18 B = 11 P = 2 R = 15 Y = 5 C = 27 Z = 2 A = 36 Q = 2 S = 1. 11. W = 14 12. D = 5 13. 3/2 = c/18; c = 27 14. 9/2 = x/16; x = 72 15. 6/20 = 54/b; b = 180 16. m/18 = 5/90; m = 1 17. 100/75 = 4/r; r = 3

gareth-patton
Download Presentation

BELLRINGER (DAY 79)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. BELLRINGER (DAY 79)

  2. Workbook page 105-106 x = 18 B = 11 P = 2 R = 15 Y = 5 C = 27 Z = 2 A = 36 Q = 2 S = 1 11. W = 14 12. D = 5 13. 3/2 = c/18; c = 27 14. 9/2 = x/16; x = 72 15. 6/20 = 54/b; b = 180 16. m/18 = 5/90; m = 1 17. 100/75 = 4/r; r = 3 18. 29/7 = x/28; x = 116 hrs 19. 150/27 = 120/x; x = 21.6 lbs 20. 2/8 = 5/x; x = 20 pints 21. 512/4 = 7680/x; x = 60sec

  3. Warm Up Determine whether the ratios are proportional. 5 8 15 24 , 1. yes 16 25 12 15 , 2. no 15 10 20 16 , 3. no 14 18 42 54 , yes 4.

  4. Review how to solve proportions by using cross products.

  5. 6 15 2 5 = For two ratios, the product of the numerator in one ratio and the denominator in the other is a cross product. If the cross products of the ratios are equal, then the ratios form a proportion. 5 · 6 = 30 2 · 15 = 30

  6. 9 15 m 5 = Additional Example 1: Solving Proportions Using Cross Products Use cross products to solve the proportion. 15 · m= 9 · 5 The cross products are equal. 15m = 45 Multiply. 15m 15 = 45 15 Divide each side by 15 to isolate the variable. m = 3

  7. 6 7 m 14 = Check It Out: Example 1 Use cross products to solve the proportion. 7 · m= 6 · 14 The cross products are equal. 7m = 84 Multiply. 7m 7 84 7 Divide each side by 7 to isolate the variable. = m = 12

  8. It is important to set up proportions correctly. Each ratio must compare corresponding quantities in the same order. Suppose a boat travels 16 miles in 4 hours and 8 miles in x hours at the same speed. Either of these proportions could represent this situation. 16 mi 4 hr 8 mi x hr 16 mi 8 mi 4 hr xhr = =

  9. 1 Understand the Problem Check It Out: Example 2 John filled his new radiator with 6 pints of coolant, which is the 10 inch mark. How many pints of coolant would be needed to fill the radiator to the 25 inch level? Rewrite the question as a statement. • Find the number of pints of coolant required to raise the level to the 25 inch level. List the important information: • 6 pints is the 10 inch mark.

  10. 2 Make a Plan Check It Out: Example 2 Continued Set up a proportion using the given information. Let p represent the pints of coolant. 6 pints 10 inches p 25 inches pints inches =

  11. 3 Solve Check It Out: Example 2 Continued 6 10 p 25 Write the proportion. = 10 · p = 6 · 25 The cross products are equal. 10p = 150 Multiply. Divide each side by 10 to isolate the variable. 10p 10 150 10 = p = 15 15 pints of coolant will fill the radiator to the 25 inch level.

  12. 4 Check It Out: Example 2 Continued Look Back 10 · 15 = 150 15 6 10 = 25 6 · 25 = 150 The cross products are equal, so 15 is the answer.

  13. Lesson Quiz for Student Response Systems 1. Use cross products to solve the proportion. = A.t = 16 B.t = 24 C.t = 32 D.t = 36 24 16 48 t

  14. Lesson Quiz for Student Response Systems 2. Use cross products to solve the proportion. = A.r = 20 B.r = 15 C.r = 10 D.r = 5 4 5 r25

  15. Closure What do you know about the cross-products of a proportion?

More Related