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【例4】有一位老人说:“把我的年龄加上14后除以3,再减去26,最后用25乘,恰好是100岁。”这位老人今年多少岁?解析:从最后一步“最后用25乘,恰好100岁”往前推,没有用25乘之前应该是100÷25=4(岁);没有减去26之前应该是4+26=30(岁),没有除以3之前应该是30×3=90(岁);把老人的年龄加上14后是90岁,那么,这位老人今年的岁数应
Example 4 An old man said: “Put my age with 14 and divide it by 3, then subtract 26, and finally multiply by 25, which happens to be 100 years old.” How old is this old man? The last step “last 25 times, exactly 100 years old ” to push forward, should be 10025 = 4 (years old) before 25 times of multiplication; should be 4 + 26 = 30 years old before subtracting 26, 30 × 3 = 90 (years old) before dividing by 3; 90 years after adding the age of the elderly to 14, then the age of the elderly should be