Could anybody please give me an answer to the following?

puts 98 + (59872 / (13*8)) * -51

PEMDAS

Parentheses, Exponents, Multiplication, Division, Addition, Subtraction

Multiplication and Division,Addition and Subtraction done in the order

they

occur in the problem.

The answer from Ruby for the above calculation is -29227

If you calculate the same problem in Microsoft Excel and a Scientific

calculator

the answer is -29262

How is this possible and why is there a difference in the answer?

Thanks

Stefan