I can't work out a few math problems The chart on the right shows the air quality of 319 cities monitored in 2004: 41.4% of them are inferior to grade 3, and 37.3% of them are better than grade 2 Tulong

I can't work out a few math problems The chart on the right shows the air quality of 319 cities monitored in 2004: 41.4% of them are inferior to grade 3, and 37.3% of them are better than grade 2 Tulong

Q: how many cities are up to or better than level 2?
319 times 41.4% = 132.066
Q: how many cities are there in the third tier?
319 times 37.3% = 118.987

The passenger car and the freight car leave from both sides of a and B at the same time. It takes 10 hours for the passenger car to complete the whole journey and 15 hours for the freight car to complete the whole journey. After the two cars meet halfway, the passenger car runs another 96 kilometers. At this time, the passenger car completes 80% of the whole journey. How many kilometers are there between a and B?

Answer: the distance between a and B is 480 kilometers

What is the sum of the square roots of all natural numbers between 1 and 100

The square roots of positive numbers are a pair of opposite numbers, and the sum is 0, so the sum of the square roots of all natural numbers between 1 and 100 is 0