Week 24 Bell Ringers & Quiz 8th grade math

Bell Ringer Tuesday 1. Calculate the number of cubic inches each figure can hold. Calculate the mean of the volumes. Calculate the range of the volumes. 4. If the dimensions of every figure are doubled, how are the volumes affected? 2 in 1 in 4 in 1 in 1 in 5 in 3 in 1 in 2 in 2

1. Calculate the number of cubic inches each figure can hold. 3

Calculate the mean of the volumes. Calculate the range of the volumes. 2 in 1 in 4 in 1 in 1 in 5 in 3 in 1 in 2 in 4

4. If the dimensions of every figure are doubled, how are the volumes affected? 2 in 1 in 4 in 1 in 1 in 5 in 3 in 1 in 2 in 5

Quiz Tuesday The first triangle is dilated to create the second triangle. What is the perimeter of the dilated triangle? 7 cm 5 cm x cm 2.5 cm 3 cm 6 cm 6

What is the perimeter of the new triangle? The first triangle is dilated to create the second triangle. What is the perimeter of the dilated triangle? Reduction 1st: 5 cm, 6 cm, 7 cm 2nd: 2.5 cm, 3 cm, x cm What is the perimeter of the new triangle? I found the scale factor used by dividing the new side by the original side. I multiplied the other dimension by the scale factor to get the missing dimension. I added the three sides together to get the perimeter. The new perimeter is 9 cm. 7

HINT: draw a picture!! Bell Ringer Wednesday You go on a hike. You hike 3 miles to the east and 4 miles north. 1. What is the quickest route back to camp? 2. How much quicker is this than hiking back the way you came? HINT: draw a picture!! 8

You go on a hike. You hike 3 miles to the east and 4 miles north. 1. What is the quickest route back to camp? 5 miles 4 miles 3 miles 9 9

You go on a hike. You hike 3 miles to the east and 4 miles north. 2. How much quicker is this than hiking back the way you came? 5 miles 4 miles 3 miles 10 10

Quiz Wednesday Out of 50 tourists, 30 tourists bought food from the ocean-side concession stand. What percentage of tourists did not buy food from the concession stand? 11

What percent did not buy food? Out of 50 tourists, 30 tourists bought food from the ocean-side concession stand. What percentage of tourists did not buy food from the concession stand? 50 tourists 30 bought 20 did not buy What percent did not buy food? To find the percent that did not buy food, I subtracted the total that did buy food from the total number of tourists. I set up a percent proportion, using the amount that did not buy food. I multiplied by a scale factor of 2. Forty percent of the tourists did not buy food. 12

Bell Ringer Thursday 1. Calculate the number of cubic inches the figure can hold. 2. Calculate the number of square inches needed to cover the figure. 3. If all the dimensions are doubled, how is the surface area affected? 4. If all the dimensions are doubled, how is the volume affected? 3.5 in 2 in 7 in 13

1. Calculate the number of cubic inches the figure can hold. 14

2. Calculate the number of square inches needed to cover the figure. 15

The new surface area is 4 times larger than the original surface area. 3. If all the dimensions are doubled, how is the surface area affected? 3.5 in 7 in 3.5 in 2 in 2 in 4 in 7 in 7 in 14 in The new surface area is 4 times larger than the original surface area. 16

Quiz Thursday The first rectangle is dilated to create the second rectangle. What is the area of the dilated rectangle? x cm 4 cm 18 cm 6 cm 17

What is the area of the new rectangle? The first rectangle is dilated to create the second rectangle. What is the area of the dilated rectangle? Enlargement 1st: 4 cm by 6 cm 2nd: x cm by 18 cm What is the area of the new rectangle? I found the scale factor used by dividing the new side by the original side. I multiplied the other dimension by the scale factor to get the missing dimension. I multiplied the length and width of the new rectangle to get the area. The new area is 216 square centimeters. 18

Bell Ringer Friday The original figure below is dilated 400%. What type of dilation occurred? Calculate the scale factor. Calculate the original area. Calculate the new area. How is the area affected? 2 in

The original figure is dilated 400%. What type of dilation occurred? Calculate the scale factor. 2 in Enlargement

The original figure is dilated 400%. Calculate the original area. 4. Calculate the new area. 8 in 2 in

The new area is 16 times larger than the original area. The original figure is dilated 400%. 5. How is the area affected? 8 in 2 in Say NO to Oreos! The new area is 16 times larger than the original area.

Quiz Friday Two figures are similar. The scale factor is ½. If the volume of the larger figure is 48 in3, what is the volume of the smaller figure?

What is the volume of the smaller figure? Two figures are similar. The scale factor is ½. If the volume of the larger figure is 48 in3, what is the volume of the smaller figure? Reduction Scale factor: ½ Volume of large: 48 cubic in What is the volume of the smaller figure? I cubed the scale factor since volume involves 3 dimensions. I set up a proportion with the volume scale factor. I used the volume of the larger figure and the volume scale factor to find the volume of the smaller figure. The volume of the smaller figure is 6 cubic inches. 24