Answer:
Sandra need to score at least <u>56%</u> in her fifth test so that her average is 80%.
Step-by-step explanation:
Given:
First 4 test scores = 87%, 92%, 76%,89%
Average targeted = 80%
We need to find the minimum score she needs to make on fifth test to achieve average of at least 80%.
Solution:
Let the minimum score she needs to make in fifth test be 'x'.
Total number of test = 5
Now we know that;
Average is equal to sum of all the scores in the test divided by number of test.
framing in equation form we get;
Multiplying both side by 5 we get;
Subtracting both side by 344 we get;
Hence Sandra need to score at least <u>56%</u> in her fifth test so that her average is 80%.
Step-by-step explanation:
Use the quadratic formula
=
−
±
2
−
4
√
2
x=\frac{-{\color{#e8710a}{b}} \pm \sqrt{{\color{#e8710a}{b}}^{2}-4{\color{#c92786}{a}}{\color{#129eaf}{c}}}}{2{\color{#c92786}{a}}}
x=2a−b±b2−4ac
Once in standard form, identify a, b and c from the original equation and plug them into the quadratic formula.
2
2
+
6
+
4
=
0
2x^{2}+6x+4=0
2x2+6x+4=0
=
2
a={\color{#c92786}{2}}
a=2
=
6
b={\color{#e8710a}{6}}
b=6
=
4
c={\color{#129eaf}{4}}
c=4
=
−
6
±
6
2
−
4
⋅
2
⋅
4
√
2
⋅
2
x=\frac{-{\color{#e8710a}{6}} \pm \sqrt{{\color{#e8710a}{6}}^{2}-4 \cdot {\color{#c92786}{2}} \cdot {\color{#129eaf}{4}}}}{2 \cdot {\color{#c92786}{2}}}
x=2⋅2−6±62−4⋅2⋅4
brainliest and follow and thanks
Answer:
60
Step-by-step explanation:
5+5+5+5+5+5+5+5+5+5+5+5
Answer:
0.715
Step-by-step explanation:
