Track / Stage 4 / 244 of 340 #504 of 1964

Problem 504

AMC 12 late, AIME early

Combinatorics Difficulty 4.9 Find the answer

(3 points) From five stamps with a face value of 1 yuan and four stamps with a face value of 1.60 yuan, if one or several stamps are taken, the number of different postage amounts that can be formed is $\qquad$ kinds.

Your answer

A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.

Official solution

【Answer】Solution: According to the analysis, we get: $6 \times 5-1=29$ (types);

Answer: 29 different postage rates can be formed. Therefore, the answer is: 29.

Source: NuminaMath-1.5, licensed Apache-2.0. Statement reproduced verbatim; metadata (topic, difficulty, ordering) added by this project.