The answer is 3. I hope this help!
Answer:
10. First you multiply both sides by 3, making it 2x + 5 = 24
Then you subtract 5 from both sides making it 2x = 19
You dive both sides by 2 making x = 9.5
The answer is x = 9.5
11. First you need to find how much you need to pay each year. 12,000 x 0.05
you can make it easier by changing it to 120 x 5 = 600
You need to pay that for three years so 600 x 3 = 1800
Plus you need to pay the original money. 12,000 + 1,800 = 13,800
The answer is $13,800
12. First you change kilometers into centimeters. 172 km is 172,000 meters. 172,000 meters is 17,200,000
Then, you need to do 17,200,000 ÷ 500,000 but you can make it simple and do 172 ÷ 5 = 34.4
The answer is 34.4 cm
So firstly, I'm going to be converting the mixed number into an improper fraction. To do this, multiply the whole number by the denominator and then add that product with the numerator and that will be your new numerator. In this case:
3 × 8 = 24, 24 + 3 = 27. 
Now since they have the same denominator, you can subtract the numerators.

Now simplify the number as such:

<u>In short, your answer is -17/4, or -4 1/4.</u>
(40+x)/2=60
40 +x = 120
x = 80
check :
40+80 = 120
120/2 = 60
so his second round needs to be 80 mph
The answer should be 2 and 1/3