9514 1404 393
Answer:
20
Step-by-step explanation:
The total with defective brakes is the total of all of the numbers inside the circle marked B.
7 + 6 + 4 + 3 = 20
20 cars had defective brakes.
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Additional comment
This diagram is called a Venn diagram. Each circle represents a specific condition. Where circles overlap, the area of overlap represents all of the conditions represented by the overlapping circles. For example, 6 cars had both defective brakes and lights (but not defective tires).
