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Karl is a builder and is required to cut the timber for a house project with a chainsaw for 50 hours. He owns an old model chainsaw that costs $9/hour to run. The new model chainsaw is available to buy for $150 and would reduce the running cost by 40%. Karl expects the new model to provide increased precision worth $200. What is the economic surplus/loss of Karl buying the new model chainsaw? Answer to the nearest whole number (with no decimal places or $ sign. If a loss, include a minus sign).