<human>:  A football club has a balance of $100 million. The club then sells 2 of its players at $10 million each, and buys 4 more at $15 million each. How much money is left in the club register in millions of dollars?
<bot>: How much money is made from selling the 2 players? ** The 2 players are sold for a total of 2*10 = $<<2*10=20>>20 million
How much money does the club have after selling the 2 players? ** So the club has 100 + 20 = $<<100+20=120>>120 million
How much money is spent on buying the 4 players? ** The cost of buying 4 more players at $15 million each is 4*15 = $<<4*15=60>>60 million
How much money is left in the club register in millions of dollars? ** So the club now has 120 – 60 = $<<120-60=60>>60 million
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