Answer:
here your answer
Step-by-step explanation:
let cp of one pen be x
cp of 5 pen = 5x
cp of 5 pen = sp of 4 pen
5x = sp of 4 pen
4x = cp of 4 pen ( cp of 1 pen = x)
profit = 5x-4x
= x
profit % = profit / cp ×100 = x/4x × 100
= 25 %
Answer:
x=1/4
y=1/2
Step-by-step explanation:
Given:
-2.4x+3.6y=1.2
2.4x + 1.2y=1.2
-2.4x+3.6y=1.2
Divide through by 1.2
-2x+3y=1
2.4x + 1.2y=1.2
Divide through by 1.2
2x+y=1
-2x+3y=1 (1)
2x+y=1 (2)
From 2
y=1-2x
Substitute y=1-2x into (1)
-2x+3y=1
-2x+3(1-2x)=1
-2x+3-6x=1
-8x=1-3
-8x=-2
Divide both sides by -8
x=1/4
Substitute x=1/4 into (2)
2x+y=1
2(1/4)+y=1
2/4+y=1
1/2+y=1
y=1-1/2
y=1/2
x=1/4
y=1/2
The diameter of the circle would be a line going through the center of the circle connecting to both sides.
The radius of a circle would be a line only going to the the center, or in other words, half the circle.
I hope this makes sense!
Answer:
Kevin needs 96 points on his last test to raise his mean test score to 90 points.
Step-by-step explanation:
we know that
The mean score is the total of all scores divided by the total number of tests.
Let
x_1 ----> the score in the first math test
x_2 ----> the score in the second math test
x_3 ----> the score in the third math test
x_4 ----> the score in the fourth math test
we have
After taking the first 3 tests, his mean test score is 88 points
so
----> equation A
How many points does he need on his last test to raise his mean test score to 90 points?
so
----> equation B
substitute equation A in equation B
solve for x_4
Therefore
Kevin needs 96 points on his last test to raise his mean test score to 90 points.