question: Jane planted a beanstalk in her backyard. After the first week, it was 3 inches tall. It doubled in height the second week. It grew another 4 inches in the third week. How tall was the beanstalk after 3 weeks?
answer: It was 3 inches tall after the first week.
  After the second week, it was 2 * 3 inches = <<2*3=6>>6 inches tall.
  After the third week, it was 6 inches + 4 inches = <<6+4=10>>10 inches tall.
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