Help with percentages

Since A has already spent all the money needed their final amount will remain $860(Put$ in front of the number). We know that 860 has to be 80% of the actual end total. ie .80 * total = 860 we can divide .80 from both sides and get that the total = 1075. Subtract the money already spent and $1075 -$1010 = $65, gives you the additional money that B must spend to be 20% of the total Just make 860 into 80% of the total, instead of 85.1%. So 20% would be 215, and B has to spend$65 more now.