Answer: There are 126 red key chains.
Step-by-step explanation:
1. You know that 10% are yellow, then:
350*0.1=35 (35 key chains are yellow).
2. And you know that of the remaining key chains 3/5 there are green.
The remaining is:
350-35=315
Then:
325*3/5=189 (189 key chains are green).
3. Then, the number of key chains that are red is:
350-35-189=126 (126 key chains are red).
