Final answer:
About 23% of all U.S. families in 2021 were headed by single mothers, indicating a significant number of them may have relied on welfare to get by.
Step-by-step explanation:
According to data in the National Journal, about 23% of all U.S. families in 2021 were headed by single mothers. The poverty rate among single-parent households tends to be relatively high. This indicates that a significant number of mothers raising children by themselves may have relied on welfare to get by, although the specific percentage cannot be determined from the information provided.