Answer:
15 answers
Step-by-step explanation:
To solve this question we need to set up an equation.
Let's name the number of incorrect answers x.
<u>We can set up an equation that's essentially:</u>
(Points for correct answer)*(number of correct answers)+(points for incorrect answer)*(number of incorrect answers)=final score
When we plug in our numbers and variables it looks like this:
5(3)+(-2x)=-15
Simplify
15-2x=-15
Subtract 15 from both sides
-2x=-30
Divide both sides by -2
x=15
This means Smitha attempted 15 wrong answers, and that there were 18 questions in total.
Answer:
√7
Step-by-step explanation:
2/5, 0.404040 and 0.286 are all rational as they all can be expressed in fraction form (0.4040 can be expressed as 40/99 and 0.286 as 286/1000 (can simplify but I didn't)) sqrt7 is the only irrational number.
Answer:
Step-by-step explanation:
If you would tell me the whole problem I could answer it
This problem can be solved by the chicken rabbits method or you can just do simple algebra.
I.) Chicken and rabbits method
First assume all 110 coins are dimes and none are quarters.
We will have a total value of 11 dollars
Now for each dime we switch out for a quarter, we adds 15 cents to the total value.
18.50-11=7.50 dollars
There are 750/15=50 group of 15 cents in the 7 dollars and 50 cents.
This also meant that we need to switch out 50 dimes for 50 quarters.
So we have 50 quarters.
That first method is very good and very quick once you get the hang of it, now I'm going to show you the algebraic way to solve this.
Let's say there are x dimes and y quarters.
Set up equation
x+y=110
10x+25y=1850
Now solve multiply first equation by 10
10x+10y=1100
subtract
15y=750
y=50
Now we set the numbers of quarters to y so the answer is 50 quarters.
I personally recommend using algebra whenever you can because the practice is very important and you will eventually get really fast at setting up and solving equations. The first method is faster in this case but the second is more generalize, hope it helps.
