Answer:
(D)6 1/2 lbs
Step-by-step explanation:
[tex]\text{Weight of the quartz = }81 \dfrac{9}{40} \text{ lbs}\\\dfrac{9}{40}=0.225 \\$Therefore:$ 81 \dfrac{9}{40} \approx 81.25\text{ lbs (to the nearest 1/4 lbs)}\\\text{Weight of the granite = }74 \dfrac{26}{36} \text{ lbs}\\ \dfrac{26}{36}=0.722 \\$Therefore:$74 \dfrac{26}{36} \approx 74.75\text{ lbs (to the nearest 1/4 lbs)}[/tex]
Difference = 81.25 - 74.75
=6.5 lbs
The correct option is D.
