Review of Scale Factor

Review of Scale Factors

Equivalent Fractions

When you find equivalent fractions, you divide the numerator and denominator by the GCF of the fraction.

Multiple Choice

Find an equivalent fraction to $$\frac{2}{4}$$

(What number can you divide 2 and 4 by?)

• $$\frac{1}{2}$$

• $$\frac{2}{2}$$

• $$\frac{1.5}{2}$$

• The fraction is already simplified

Multiple Choice

Find an equivalent fraction to $$\frac{9}{21}$$

(What number can you divide 9 and 21 by?)

• The fraction is already simplified

• $$\frac{1}{3}$$

• $$\frac{3}{7}$$

• $$\frac{6}{12}$$

Multiple Choice

Find an equivalent fraction to $$\frac{15}{20}$$

(What number can you divide 15 and 20 by?)

• The fraction is already simplified

• $$\frac{6}{8}$$

• $$\frac{1}{2}$$

• $$\frac{3}{4}$$

Scale Factor Review

The scale factor is a ratio (fraction) that is used to change the size of a shape.

Scale Factor Review

​Start by picking a side on the scaled model

Multiple Choice

What side corresponds to (matches) Side NL in the triangle to the right?

• RQ

• RS

• SQ

• RS

Multiple Choice

What value represents the scale factor if the triangle on the right is the new figure?

(Find $$\frac{Length\ of\ SQ}{Length\ of\ NL}$$

• $$\frac{4}{12}$$

• $$\frac{4}{3}$$

• $$\frac{3}{9}$$

• $$\frac{3}{4}$$

Multiple Choice

What side corresponds to (matches) side EH on the trapezoid to the right?

• ML

• KL

• JM

• JK

Multiple Choice

What value represents the scale factor for the trapezoids? The figure on the right is the scaled copy.

(Find the ratio of $$\frac{JM}{EH}$$ and simplify)

• $$7$$

• 2

• $$\frac{1}{2}$$

• $$\frac{1}{4}$$

Perimeter of Scaled Figures

To find perimeter, you find the sum of all sides (add)

Multiple Choice

Which of the following represents the ratio you could use to find the scale factor if the right figure is the new (scaled) figure?

• $$\frac{ST}{PR}$$

• $$\frac{UT}{RQ}$$

• $$\frac{SU}{RQ}$$

• $$\frac{SU}{PQ}$$

Multiple Choice

Find the scale factor for the triangles (fully simplify the ratio $$\frac{UT}{RQ}$$ )

• $$\frac{12}{8}$$

• $$\frac{3}{2}$$

• $$\frac{2}{3}$$

• $$\frac{5}{2}$$