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3:2 2:3 The ratio of the lengths of corresponding sides in similar figures (same shape but different size) is called scale factor. It may be expressed as a fraction, decimal, percent, or whole number. It may be large number first or small number first. What would NOT be a scale factor for the shapes below? 3 cm 2 cm .6666667 2:1 6 cm by 10 cm 2 cm by 3 cm Since a scale factor may be large-to-small or small-to- large and in fraction, percent, or decimal form, all answers were right except for 2:1. Neither 3:2 or 2:3 will simplify to 2:1.
A rectangle has sides of 3 cm and 5 cm. A similar rectangle has a scale factor of 1:2 or 50%. Find its length and width. 1.5 cm by 2.5 cm 2 cm by 2.5 cm 6 cm by 10 cm 2 cm by 3 cm A rectangle has sides of 3 cm and 5 cm. A similar rectangle has a scale factor of 1:2 or 50%. Find its length and width. Since 50% equals 0.5 and 1/2, multiply both numbers separately by 0.5 or 1/2. We can divide by the reciprocal 2 also. The answer is 1.5 cm. by 2.5 cm.
A rectangle has sides of 3 cm and 5 cm. A similar rectangle has a scale factor of 200%. Find its dimensions. 2 cm by 2.5 cm 1.5 cm by 2.5 cm 80 cm A rectangle has sides of 3 cm and 5 cm. A similar rectangle has a scale factor of 200%. Find its dimensions. 200% equals 2, so multiply the perimeter by 2. The answer is 6 cm by 10 cm.
If we know one shape's perimeter, that both are similar, and the scale factor, we can solve for the other shape's perimeter by multiplying each number by the scale factor. If the first shape has a perimeter of 16 cm. and the scale factor is 50%, the second shape's perimeter is... 32 cm 8 cm 80 cm 32 cm 3200 cm The first shape has a perimeter of 16 cm. and the scale factor is 50%, so multiply 16 by 0.5, 1/2, or divide by the reciprocal of 2. The answer is 8 cm.
If the perimeter is 16 cm. and the scale factor 200%, the perimeter of the similar shape is... 8 cm 80 cm 45 square centimeters 90 square centimeters The perimeter of the first shape is 16 cm. and the scale factor 200% (which equals 2). The perimeter of the similar shape is 32. Multiply 16 by 2.
Because area is in square units, we have to square the scale factor before multiplying it by the area of the first shape. Our original shape was 3 cm. by 5 cm. Therefore its area is 3 x 5 or 15 square centimeters. A similar shape with a scale factor of 3 would have an area of... 135 square centimeters 32 square centimeters 9.6 square centimeters 24 square centimeters Because area is in square units, we have to square the scale factor before multiplying it by the area of the first shape. Our original shape was 3 cm. by 5 cm. Therefore its area is 3 x 5 or 15 square centimeters. A similar shape with a scale factor of 3 would have an area of...Square the scale factor 3. It becomes 3 x 3 or 9. Then multiply 9 times 15. The answer is 135 square centimeters.
If the original area was 60 square centimeters and the scale factor 40%, the new shape's area would be... 96 square centimeters 2.4 square centimeters 60 x 2 x 2 x 2 60 x 3 x 3 x 3 If the original area was 60 square centimeters and the scale factor 40%, the new shape's area would be... 60 x .4 x .4 = 9.6.
Because volume is in cubic units, we have to cube (to the 3rd power) the scale factor to convert volume of similar 3-dimension shapes. If the first has a volume of 60 cubic units and the scale factor is 2, the volume of the second shape would be 60 x 2 x 2 x 2. What if the first shape has a volume of 60 cubic units and the scale factor is 3... 60 x 2 x 2 60 x 3 x 3 60 x 1/4 x 1/4 x 1/4 60 x .25 x .25 Because volume is in cubic units, we have to cube (to the 3rd power) the scale factor to convert volume of similar 3-dimension shapes. If the first has a volume of 60 cubic units and the scale factor is 2, the volume of the second shape would be 60 x 2 x 2 x 2. What if the first shape has a volume of 60 cubic units and the scale factor is 3...60 x 3 x 3 x 3.
The volume of the first shape is 60 cubic units and the scale factor is 25%... 60 x .25 60 ÷ 0.25 2 cm. by 5 cm. 20 cm. 50 cm. The volume of the first shape is 60 cubic units and the scale factor is 25%...Volume is in cubic units so we cube the scale factor. 25% equals the fraction 1/4. Multiply 1/4 or 0.25 by itself three times and then times the first shape's area.
If the first shape is 4 cm. by 10 cm and the scale factor is 3, what are the new shape's dimensions? 90 cm. by 36 cm. 12 cm. by 30 cm. |