Say Whether a Quantity Is Per Item or Per Set

Say whether a number applies to each item or to the whole set before you calculate or rewrite it. A clear quantity needs both a count and an explicit relationship to the items it describes.

Consider this draft:

Three envelopes with four labels.

Does each envelope contain four labels, or do the three envelopes contain four labels altogether? The sentence leaves that relationship unstated. Choosing either reading changes what you can say about the total.

NIST's guide to quantity wording, section 7.2, recommends rearranging an ambiguous quantity statement. The two cases below apply that narrow writing principle to original fictional examples. They are independent sets of supplied facts, rather than counts we observed or successive versions of one set.

Case A: Four Labels in Each Envelope

Supplied facts: There are exactly three envelopes, E1, E2 and E3. Each contains exactly four labels: E1 has four, E2 has four and E3 has four.

Here the number four applies to each envelope. Adding the three known counts gives the total:

4 + 4 + 4 = 12 labels. Equivalently, 3 envelopes × 4 labels per envelope = 12 labels in total.

Finished copy:

Each of the three envelopes contains four labels, for 12 labels in total.

The word “each” establishes the per-envelope count. “In total” names the count across the whole set. Both statements follow from the supplied facts, so you can include both when your reader needs them.

Case B: Four Labels Across the Whole Set

Supplied facts: There are exactly three envelopes, E1, E2 and E3. Together they contain exactly four labels. The number in each envelope is not recorded.

Here four already counts the labels across all three envelopes. The supported total is four labels; the individual envelope counts remain unknown.

Finished copy:

The three envelopes contain four labels in total; the number in each envelope is not recorded.

Multiplying four by three would change the scope of the supplied count. Dividing four by three would not recover the actual count in each envelope, either. There is no supplied equal-distribution rule, and these are whole labels, so leave their placement unspecified.

Resolve the Meaning Before Repairing the Sentence

The original draft alone does not tell you which case is intended. Adding “each” would choose Case A; adding “in total” would choose Case B. Either repair needs the corresponding facts first.

For your own copy, identify the objects, the quantity and what that quantity applies to. Then use each item or the whole set explicitly where the relationship could be unclear. Calculate a total only from the scope you actually have, and retain an unknown distribution when the source supplies only a set total.

When you plan a post around a reader's question, decide whether the reader needs an individual count, a set total or both. Keep that distinction in your article brief, then use the blog-writing guide to connect the finished sentence with its explanation.