Paula has $54. She bought some pencils, each costing $0.75, and a paper ream for $2.50. She is left with $42.50 after buying pencils and the ream of paper. She uses the equation Syntax error from line 1 column 49 to line 1 column 73. Unexpected 'mathsize'. to find the number of pencils she bought. How many pencils did Paula buy?