Lizzy: Sara sent letters to her friend in China every month. She sent 6 letters in January, 9 letters in February, and in March she sent triple the number of letters she sent in January. How many letters does Sara send?.
Me: Hmmm, let me think. I think this is the detailed solution:
Combining January and February, Sara sent 6 + 9 = 15 letters. In March, she sent 3 * 6 = 18 letters. Altogether, Sara sent 15 + 18 = 33 letters. Final answer: 33.