Answer:
13.36
Step-by-step explanation:
I will first create a table
X. Y. XY. X²
1. 20. 20. 1
2. 24. 48. 4
3. 35. 105. 9
4. 46. 184. 16
5. 67. 335. 25
6. 80. 480. 36
1. 12. 12. 1
2. 34. 68. 4
3. 34. 102. 9
5. 78. 430. 25
ΣX = 32
ΣY = 430
ΣXY = 1744
ΣX² = 130
n = 10
The formula for regression line is given as :
Y = a + bX
a = intercept
b = slope
The question requires us to find b which is the slope.
b = nΣXY-ΣXΣY/nΣX²-(ΣX)²
= 10x1744-32x430/10x130-(32)²
= 17440-13760/1300-1024
= 3680/276
= 13.36
b = 13.36
Answer:
Step-by-step explanation:
Use the formula to find the z-score, then go to the table that will give you the probability that the value is less than this z-score.

The probability that the value lies to the left of 1 on a standard bell curve is 84.1345%, or 84%, the third choice down.
<u>Direct Variation:</u> 

when y = 7: 
14 = 15x

<u>Inverse variation:</u> y*x = k
15 * 2 = k
30 = k
when y = 7: 7 * x = 30

8z +3 - 2z < 51
6z + 3 < 51
-3. -3
6z < 48
-- ---
6. 6
z<8
Answer: 0.15 is equivalent to 3/20