To find this answer, we need to multiply 3.57 by 12.

Therefore, 12 planks will cost $42.84.
Answer:
a 26
b 8 2/3
Step-by-step explanation:
a) 4 1/3 * 6
Change the mixed number to an improper fraction
(3*4+1)/3 *6
13/3 *6
= 78/3
= 26
b) 2 3/5 * 3 1/3
Change the mixed numbers to improper fractions
(5*2+3)/5 * (3*3+1)/3
13/5 * 10/3
130/15
Top and bottom divide by 5
26/3
Change back to a mixed number
3 goes into 26 8 times (3*8 =24) with 2 left over
8 2/3
Start with your lowest numbers, 3 bracelets have 24 beads. The easiest way to find your answer is to find out how many beads are on 1 bracelet. So 24/3 will give us that answer. 24/3=8. and then multiply 7 by 8 to get 56. then check your answer to make sure it fits.
3 x 8 = 24
5 x 8 = 40
7 x 8 = 56
9 x 8 = 72