Answer:
Dave is 18 and his sister is 6.
Step-by-step explanation:
If you do 38 -7x2 you can work out the combined ages of them now which is 24 (you have to do 7x2 because there are two of them and its seven years in the future). Then you can work out their ages using a ratio. Dave’s age : his sister’s age is 3:1 so if you divide 24 by 4 (3+1 = 4 so your can work out one portion of their age) you can find out how old the sister is which is 6. Times that by 3 to get Dave’s age which is 18. A formula for this (where x is his sisters age) would be 3x=38-7x2 which cancels down to 6.
Answer:
0.4444444
Step-by-step explanation:
2/3 x 2/3 = 0.4444 repeating!
Hope this helps!
<u><em>Answer: B. 2/5 *The answer must have a fraction.</em></u>
Explanation:
Slope-intercept form: → 
m: represents the slope and is constant.
b: represents the y-intercept.
Used rise/run.



You had to find the slope by using formula.


subtract by the numbers and add the numbers too.


Hope this helps!
Answers:
11. 48%
12. 25%
13. 36%
15. 93%
16. 99%
17. 0.16%
18. 160%
19. 85%
Work for 19:
The chart is incorrect because it calculates 40% of 34 instead of 40 percent of x (we got 85% for our answer but I'm using x as the unknown number) results in the number of 34.
Percentage of 40% of what number = 34?
40% of what number = 34 is equivalent to: 40% × ? = 34
--------------------------
40% × ? = 34
? =
34 ÷ 40% =
34 ÷ (40 ÷ 100) =
(100 × 34) ÷ 40 =
3,400 ÷ 40 =
85
Proof:
If 40% × 85 = 34 =>
Divide 34 by 85...
... And see if we get as a result: 40%
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20. 21 students
Step-by-step explanation:
I hope I helped, and I always appreciate brainliest!!! ;)
9514 1404 393
Answer:
(C) Step 1: 15x − 20 = 1; Step 2: 15x = 21
Step-by-step explanation:
The first step is to eliminate the parentheses, using the distributive property.
5(3x − 4) = 1
15x -20 = 1
The second step is to add 20 to both sides of the equation.
15x = 21
This pair of steps is shown in the 3rd choice.
_____
<em>Comment on the answers</em>
The distributive property seems to be applied incorrectly a lot of the time. Here, you can choose the correct answer by looking at the result of properly applying the distributive property: 5(3x-4) = 15x-20. Only the correct choice has this as the first step.