Answer:
The choice three ;

Step-by-step explanation:

<span>The mean of a set of data is 148.87 and its standard deviation is 68.29. Find the z score for a value of 490.19
the z-score is given by:
z=(x-</span>μ<span>)/</span>σ
plugging in the values in the expression we get:
z=(490.19-149.87)/68.29
z=340.32/68.29
z=4.9835
A. 38
Let X = seventh graders
6th graders are twice the number of 7th graders; therefore, 6th graders will be 2X.
The total number of students is 57.
2X + X = 57
3X = 57
X = 57 / 3
X = 19
IF X represents the 7th graders; there are 19 seventh graders present.
Since 6th graders are represented by 2X; Then, 2 * 19 = 38 is the number of 6th graders present.
Add both numbers to check: 19 + 38 = 57.
Answer:
LCD-3x(x+2)
Final answer- x2-4x+4/ 3x2+6x
Step-by-step explanation:
okay so LCD is 3*x*(x+2)
= 3x(x+2)
so multiyling the fist expresion by x+2 and the second by x we get
2x+4+ x2-6x/ 3x(x+2)
= so
x2-4x+4/3x(x+2)
x2-4x+4/ 3x2+6x
if my answer helps please mark as brainliest.