Answer: The sash will have 20 diamonds when it is completed.
Step-by-step explanation:
Given: The length of American sash= 8 feet
Since, Joseph wants to add a diamond shape every 0.4 ft along the sash.
Therefore, the number of diamonds he will need to complete the sash= [tex]\frac{8}{0.4}[/tex]
⇒ The number of diamonds he will need to complete the sash= [tex]\frac{80}{4}=20[/tex]
Hence, the number of diamonds he will need to complete the sash= 20
