Question

Difficulty: EasyNails and Brads

A cabinetmaker uses the standard pennyweight formula, Length=d4+0.5 inches\text{Length} = \frac{d}{4} + 0.5\text{ inches}, to determine fastener dimensions for sizes up to 10d10\text{d}, where dd represents the penny size number. What is the total length, in inches, of a 4d4\text{d} nail?

Answer: 1.5 inches

Answer

The total length of a 4d4\text{d} nail is 1.5 inches1.5\text{ inches}.
Using the standard carpentry formula for nails between 2d2\text{d} and 10d10\text{d} (Length=d4+0.5 inches\text{Length} = \frac{d}{4} + 0.5\text{ inches}), substituting d=4d = 4 yields 44+0.5=1+0.5=1.5 inches\frac{4}{4} + 0.5 = 1 + 0.5 = 1.5\text{ inches}.

Step-by-Step Solution

1
Identify the variable dd representing the penny rating.
d=4d = 4
The question specifies a 4d4\text{d} nail.
2
Substitute d=4d = 4 into the nail length formula Length=d4+0.5\text{Length} = \frac{d}{4} + 0.5.
Length=44+0.5\text{Length} = \frac{4}{4} + 0.5
The standard empirical formula relates penny size to physical inch length.
3
Perform arithmetic evaluation to find the final length.
1.5 inches1.5\text{ inches}
Dividing 44 by 44 gives 11, and adding 0.50.5 yields 1.51.5.

Key Concept

Nail Pennyweight (d) Sizing System
Estimated Time:45s
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