A tin of paint covers a surface area of 70m2.
Each tin costs £5.20.
The entire surface of a solid cylindrical rod with diameter 7m and height 13m needs to be painted.
Find the minimum cost of painting the rod.
Answer: 440 grams for 1.54 is the better value
Explanation:
Take the price and divide by the number of grams
1.54 / 440 =0.0035 per gram
1.26 / 340 =0.003705882 per gram
0.0035 per gram < 0.003705882 per gram