Answer: 6.6kg
Step-by-step explanation:
6 blue slabs have a mean weight of 7 kg. The total weight of the 6 blue slabs will be:
= 6 × 7kg
= 42 kg
3 yellow slabs have a mean weight of 5 kg. The total weight of the 3 yellow slabs will be:
= 3 × 5kg
= 15kg
1 grey slab has a mean weight of 9kg.
To get the mean of the 10 slabs, we add their total weights together and divide by 10. This will be:
= (42kg + 15kg + 9kg)/10
= 66kg/10
= 6.6kg