When ever you have percentages, it should be helpful to bear in mind you can express them as multipliers. In this case, it will be helpful.
So, if we let:
a = test score
b = target score
then, using the information given:
a = 1.1b + 1
a = 1.15b - 3
and we get simultaneous equations.
'1.1' and '1.15' are the multipliers that I got using the percentages. Multiplying a value by 1.1 is the equivalent of increasing the value by 10%. If you multiplied it by 0.1 (which is the same as dividing by 10), you would get just 10% of the value.
Back to the simultaneous equations, we can just solve them now:
There are a number of ways to do this but I will use my preferred method:
Rearrange to express in terms of b:
a = 1.1b + 1
then b = (a - 1)/1.1
a = 1.15b - 3
then b = (a + 3)/1.15
Since they are both equal to b, they are of the same value so we can set them equal to each other and solve for a:
(a - 1)/1.1 = (a + 3)/1.15
1.15 * (a - 1) = 1.1 * (a + 3)
1.15a - 1.15 = 1.1a + 3.3
0.05a = 4.45
a = 89
Answer:
x = √39
General Formulas and Concepts:
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
Equality Properties
<u>Trigonometry</u>
- [Right Triangles Only] Pythagorean Theorem: a² + b² = c²
Step-by-step explanation:
<u>Step 1: Identify</u>
Leg <em>a</em> = <em>x</em>
Leg <em>b</em> = 5
Hypotenuse <em>c</em> = 8
<u>Step 2: Solve for </u><em><u>x</u></em>
- Substitute [PT]: x² + 5² = 8²
- Isolate <em>x</em> term: x² = 8² - 5²
- Exponents: x² = 64 - 25
- Subtract: x² = 39
- Isolate <em>x</em>: x = √39
Alternate interior angles are equal, thus the given alternate interior angle is 80 degrees.
Therefore, x = 80 - 15 = 65 degrees.
In order to move a number that is multiplied or divided by the variable<span>, you must do the inverse to both sides. That means, if the number is multiplied, you must divide it by both sides. If it's divided, you must </span>multiply<span> it by both side. steps so that you can apply them to more complex </span>problems<span>.</span>
X + y = 20---- 1
x - y = 8----- 2
From 1+2
2x = 28
x = 14
Substitute x in eq.2
14 -y = 8
y = 6
Ans : x= 14 , y= 6
