Question

Linda had been collecting stamps for 5 weeks and had 25 stamps in her stamp book. Her book holds 64 stamps. She then began purchasing 3 stamps each week.
What was the total number of weeks that it took Linda to fill her stamp book?


weeks

Answer 1

I don't know what method they want you to use to find this, but you could just keep adding 3 to the previous number. Week 5 she has 25. Week 6 she has 28. Week 7 she has 31. 8, 34. 9, 37. 10, 40. 11, 43. 12, 46. 13, 49. 14, 52. 15, 55. 16, 58. 17, 61. And finally, at week 18, she will have 64 stamps.