Answer:
Option B.
Step-by-step explanation:
It is given that Lisa needs 250 yards of yarn to knit a hat.
She has 185 yards of yarn and needs to buy the rest.
Let y to be the number of yards of yarn she needs to buy.
Number of yards of yarn she needs to buy + Number of yards of yarn she has = 250
Subtract 185 from both sides.
The required equation is
and solution is
.
Therefore, the correct option is B.