Answer:
20 mph
Step-by-step explanation:
First problem:
The new speed is 26 mph.
The old speed was x.
The new speed is 30% higher than the old speed.
1.3x = 26
x = 20
Answer: 20 mph
Second problem:
A number, perhaps a percent or a fraction, is missing from the problem.
Interesting question. Good to know for computer science.
Suppose you have a function like
an = 3x - 2 Try the first couple
a1 = 3(1) - 2
a1 = 3 - 2
a1 = 1
a2 = 3(2) - 2
a2 = 6 - 2
a2 = 4 So each term differs by 3
a2 - a1 = 3
an = a_(n - 1) + 3
a3 = a2 + 3
a3 = 4 + 3
a3 = 7
a4 = a3 + 3
a4 = 7 + 3
a4 = 10
a5 = a4+ 3
a5 = 10 + 3
a5 = 13
I'll do one more and then check it.
a6 = a5 + 3
a6 = 13 + 3
a6 = 16
a6 = 3x -2
a6 = 3*6 - 2
a6 = 18 - 2
a6 = 16 which checks.
So the general formula is
an = a_(n - 1) * k if you were multiplying or
an = a_(n - 1) + k if you were adding. The key thing is that you are working with the previous term.
Answer:
10 SENIORS
Step-by-step explanation:
x=# of seniors
y=# of juniors
x+y=23, x=2y-7
- plug the value of x in the second equation into the first
- (2y-7)+y=23
- Remove parentheses
- 2y-7+y=23
- Combine like terms
- 3y-7=23
- Add 7 to BOTH sides
- 3y=30
- divide BOTH sides by 3
- 3y/3=30/3
- y=10
- There are 10 juniors in the class
- FINAL STEPS
- Plug y (which is 10) into the first equation
- x+y=23
- x+10=23
- subtract 10 from BOTH sides
- x=13
- Since X equals the number of seniors, there are 10 seniors in the class
It's D because I don't see no solution
