I NEED HELP WITH THESE 4 ASAP

Tamir bought 2 1/2 pounds of fish at $5.50 per pound, and two bananas at $0.45 each.

tia_tia [17]

0.45+0.45= $0.90 + 5.50x2+2.25=$13.25 13.25+0.90 =$14.50 he would get $5.50 back out of the 20$ spent

6 0

3 years ago

Rockwell hardness of pins of a certain type is known to have a mean value of 50 and a standard deviation of 1.2.a. If the distri

zalisa [80]

Answer:

a

$P(\= X \ge 51 ) =0.0062$

b

$P(\= X \ge 51 ) = 0$

Step-by-step explanation:

From the question we are told that

The mean value is $\mu = 50$

The standard deviation is $\sigma = 1.2$

Considering question a

The sample size is n = 9

Generally the standard error of the mean is mathematically represented as

$\sigma_x = \frac{\sigma }{\sqrt{n} }$

=> $\sigma_x = \frac{ 1.2 }{\sqrt{9} }$

=> $\sigma_x = 0.4$

Generally the probability that the sample mean hardness for a random sample of 9 pins is at least 51 is mathematically represented as

$P(\= X \ge 51 ) = P( \frac{\= X - \mu }{\sigma_{x}} \ge \frac{51 - 50 }{0.4 } )$

$\frac{\= X -\mu}{\sigma } = Z (The \ standardized \ value\ of \ \= X )$

$P(\= X \ge 51 ) = P( Z \ge 2.5 )$

=> $P(\= X \ge 51 ) =1- P( Z < 2.5 )$

From the z table the area under the normal curve to the left corresponding to 2.5 is

$P( Z < 2.5 ) = 0.99379$

=> $P(\= X \ge 51 ) =1-0.99379$

=> $P(\= X \ge 51 ) =0.0062$

Considering question b

The sample size is n = 40

Generally the standard error of the mean is mathematically represented as

$\sigma_x = \frac{\sigma }{\sqrt{n} }$

=> $\sigma_x = \frac{ 1.2 }{\sqrt{40} }$

=> $\sigma_x = 0.1897$

Generally the (approximate) probability that the sample mean hardness for a random sample of 40 pins is at least 51 is mathematically represented as

$P(\= X \ge 51 ) = P( \frac{\= X - \mu }{\sigma_x} \ge \frac{51 - 50 }{0.1897 } )$

=> $P(\= X \ge 51 ) = P(Z \ge 5.2715 )$

=> $P(\= X \ge 51 ) = 1- P(Z < 5.2715 )$

From the z table the area under the normal curve to the left corresponding to 5.2715 and

=> $P(Z < 5.2715 ) = 1$

So

$P(\= X \ge 51 ) = 1- 1$

=> $P(\= X \ge 51 ) = 0$

5 0

3 years ago

What fractions are equivalent to 1/3?

ExtremeBDS [4]

Answer:

#markasbrainliest

1/3

=

2/6

=

3/9

=

4/12

=

5/15

=

6/18

=

7/21

=

8/24

=

9/27

=

10/30

=

11/33

=

12/36

=

13/39

=

14/42

=

15/45

=

16/48

=

17/51

=

18/54

=

19/57

=

20/60

=

21/63

=

22/66

=

23/69

=

24/72

=

25/75

=

26/78

=

27/81

=

28/84

=

29/87

=

30/90

=

31/93

=

32/96

=

33/99

=

34/102

=

35/105

=

36/108

=

37/111

=

38/114

=

39/117

=

40/120

=

41/123

=

42/126

=

43/129

=

44/132

=

45/135

=

46/138

=

47/141

=

48/144

=

49/147

=

50/150

=

51/153

=

52/156

=

53/159

=

54/162

=

55/165

=

56/168

=

57/171

=

58/174

=

59/177

=

60/180

=

61/183

=

62/186

=

63/189

=

64/192

=

65/195

=

66/198

=

67/201

=

68/204

=

69/207

=

70/210

=

71/213

=

72/216

=

73/219

=

74/222

=

75/225

=

76/228

=

77/231

=

78/234

=

79/237

=

80/240

=

81/243

=

82/246

=

83/249

=

84/252

=

85/255

=

86/258

=

87/261

=

88/264

=

89/267

=

90/270

=

91/273

=

92/276

=

93/279

=

94/282

=

95/285

=

96/288

=

97/291

=

98/294

=

99/297

=

100/300

3 0

3 years ago

Read 2 more answers

Find the percent decrease.Round to the nearest percent. From 97 to 75

damaskus [11]

Answer:

Step-by-step explanation:

Decrease = 97 - 75 = 22

Percentage of decrease=

$=\frac{22}{97}*100$

= 22.68

= 23%

4 0

4 years ago

Haley used unit cubes to build a rectangular prism that is 5 units long, 3 units wide, and 4 units tall. Jeremiah used unit cube

ad-work [718]

Answer:

10 units

Step-by-step explanation:

Let us find the volume of Haley's prism and compare it with the volume of Jeremiah's.

The volume of Haley's prism is:

V = 5 * 3 * 4 = 60 cubic units

Jeremiah's prism has twice the volume of Haley's:

V(J) = 2 * 60 = 120 cubic units

This implies that:

120 = 4 * 3 * h

where h = height of prism

=> 120 = 12h

=> h = 120 / 12 = 10 units

Jeremiah's prism is 10 units tall.

8 0

4 years ago