Why would you make one of the addends a tens number when solving and addition problem

If kn = 9 cm, mn = 21 cm, rs = 42 cm, and ps = 18 cm, what is the scale factor of figure klmn to figure pqrs?

Which transformations could have occurred to map △abc to △a"b"c"? a rotation and a reflection a translation and a dilation a reflection and a dilation a dilation and a rotation

Will give brainliest sum of arithmetic series (sigma notation) find the numerical answer to the summation given below. (image shown below)