Final answer:
The scale factor from Mrs. Minor's old 6ft by 8ft stall to her new 9ft by 12ft stall is 1.5, which is option a) 1.5.
Step-by-step explanation:
The scale factor from the old stall to the new stall that Mrs. Minor is designing can be determined by comparing the measurements of one dimension of the old stall to the corresponding dimension of the new stall. Since the old stall is 6 feet by 8 feet and the new one is 9 feet by 12 feet, we can compare either the length or the width to find the scale factor.
To find the scale factor, we divide the length of the new stall by the length of the old stall: 9ft ÷ 6ft = 1.5. Alternatively, we can use the width to verify this scale factor: 12ft ÷ 8ft = 1.5.
Therefore, the correct scale factor from the old stall to the new stall is 1.5, which corresponds to option a) 1.5.