which numbers are prime numbers 37,39,41,43 answer 37,41,43
John spent 1/3 of his study time doing math homework and 3/5 preparing for a history exam what fraction of his study time remains? answer 1/15
Solve for the unknown 2/7/20=1.6/ranswer 112
37,41,43 - right!
1/15 - right!
112 - right!
What are prime numbers
To determine if a number is prime or not, you need to check if it is divisible by any number other than 1 and itself. Here's how you can find the prime numbers between 37, 39, 41, and 43:
1. Start with the first number, 37:
- Check if any number between 2 and 36 divides 37. In this case, none do.
2. Move on to the next number, 39:
- Check if any number between 2 and 38 divides 39. It is divisible by 3.
- Since it is divisible by a number other than 1 and itself, it is not a prime number.
3. The third number is 41:
- Check if any number between 2 and 40 divides 41. In this case, none do.
4. The last number is 43:
- Check if any number between 2 and 42 divides 43. In this case, none do.
So, the prime numbers among 37, 39, 41, and 43 are 37, 41, and 43.
Regarding John's study time:
1. John spent 1/3 of his time doing math homework.
2. He spent 3/5 of his time preparing for a history exam.
3. To determine the fraction of time remaining, subtract the time spent on math and history from 1 (which represents the entire time).
Calculating the fraction of time remaining:
1 - (1/3 + 3/5) = 1 - (5/15 + 9/15) = 1 - 14/15 = 1/15
Therefore, 1/15 of John's study time remains.
To solve for the unknown in the equation 2/7/20 = 1.6/r:
1. Start by simplifying the expression on the left side:
- Divide 2 by 7 to get 2/7.
- Divide the result by 20: (2/7) / 20 = 2/7 * (1/20) = 2/140
2. Now, the equation becomes: 2/140 = 1.6/r
3. Cross-multiply: 2r = 140 * 1.6
4. Solve for r by dividing both sides by 2: r = (140 * 1.6) / 2 = 140 * 0.8 = 112
Therefore, the unknown value r is equal to 112.