Zhang Xiaoling learned to type on the computer. She typed 180 words in the first three minutes. After three minutes, she could type 80 words per minute. In this way, she could finish typing in 15 minutes

Zhang Xiaoling learned to type on the computer. She typed 180 words in the first three minutes. After three minutes, she could type 80 words per minute. In this way, she could finish typing in 15 minutes

Zhang Xiaoling learned to type on the computer. She typed 180 words in the first three minutes. After three minutes, she could type 80 words per minute. In this way, the answer she could finish in 15 minutes was 180 + (15-3) × 80 = 1140

What's 80 less than 2 times 280?

480 280x2-80=560-80=480

At the same time, they are multiples of 2,5,3 and all have 1. This number is greater than 50 and less than 80. This number is []

2. 5, 3, common multiple 30, 60, 90, etc
Only 60 of them fit the meaning of the question,
So this number is 60 + 1 = 61