∆abc and ∆pqr are similar. ∆abc is dilated by a scale factor of 1.25 and rotated 45° counterclockwise about point b to form ∆pqr. the side lengths of ∆abc are , 5 units; , 4.2 units; and , 4 units. match each side of ∆pqr to its length.

This is the concept of transformation of figures, given that ΔABC is similar to ΔPQR, the sides of ABC are 5 units, 4.2 units and 4 units. Since the two triangles are similar and PQR is the image of ABC under the dilation 1.25, the sides of PQR will be:
(5*1.25),(4.2*1.25),(4*1.25)
this will give us:
6.25, 5.25, 5
The length of the sides of PQR are 6.25 units, 5.25 units and 5 units

The key is the word about, they want an estimation.63 is closer to 60, 71 is closer to 7060 + 70 = 130ryan counted about 130 birds