Answer:
257 is prime.
Step-by-step explanation:
To evaluate if a number is prime, we just need to evaluate it for the prime numbers that are equal or lesser than the said number's square root.
In this case, √257 = 16.03 so we just need to see if 257 is divisible by <u>2, 3, 5, 7, 11 and 13</u> (the prime numbers that come before 16)
- 257 is odd, so it is not divisible by 2.
- The sum of its digits is 14, therefore, it is not divisible by 3.
- 257 ends in 7, therefore it's not divisible by 5.
- 257/ 7 = 36.71 so it's not divisible by 7.
- 257/ 11 = 23.36 so it's not divisible by 11
- Finally 257 / 13= 19.76 so it's not divisible by 13.
Therefore, 257 is prime.
So 161 divide 7 equals 23 so therefor he types 23 words per minutes. 23 times 20 equals 460. I think he can type 460 words in 20 minutes.
Hi
I belive you add the top side (4) plus the bottom side (9.5) witch would equal 13.5 times the hieght (3) equals 40.5 divided by 2 equals 20.25. the area is 20.25ft squared
another way to do it
4+9.5= 13.5
13.5×3= 40.5
40.5÷2= 20.25ft
Answer
D. 3m - 4/3 -2/m
<u>Explanation</u>
(9m²-4m-6) ÷ 3m = 9m²/3m - 4m/3m - 6/3m
Carry out the division, each term is divided by 3m.
9m²/3m = 3m
- 4m/3m = -4/3
- 6/3m = - 2/m
Finally you will get,
<em>3m - 4/3 -2/m</em>
