The total cost of materials can be found from a list of materials based on the market unit rate.
The correct responses are;
Reasons:
Part A: The given expression representing the purchase is presented as follows;
Purchases = 180·s + 9·p + 36·l
Where;
s = Screws
P = Posts
l = Lumber
The factored expression is found as follows;
Purchases = 180·s + 9·p + 36·l = 9 × 20·s + 9·p + 9 × 4·l, which gives;
180·s + 9·p + 36·l = 9 × (20·s + p + 4·l)
The factored expression is; 9 × (20·s + p + 4·l)
Part B: The costs are;
100 screws = $6.99
1 posts = $16.40
10 pieces of lumber = $88.20
The materials Roberto need to buy are;
180 screws, which can be obtained by buying 2 cartons of screws.
9 posts, which is obtained by buying 9 pieces of posts.
36 lumber which can be obtained by buying 4 × 10 pieces = 40 pieces of lumber.
Therefore, the, material Roberto needs to buy are;
2 cartons of screws
9 pieces of posts
40 pieces of lumber
Part C: The total cost of the materials are therefore;
2 cartons of screws × $6.99 per carton = $13.98
9 pieces of posts × $16.40 per piece = $147.6
4 Sets of 10 pieces of lumber × $88.20 per set = $352.8
The total cost = $13.98 + $147.6 + $352.8 = $514.38
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