At a retail shop, coins worth ₹2,160 were collected in a day, including ₹1, 2, 5, and 10 coins. If the number of ₹2 coins was 10 more than the number of ₹10 coins, 20 more than the number of ₹5 coins, but 20 less than the number of ₹1 coins, then what was the number of ₹10 coins?