Technical Math for Radiography

Technical Math For Radiography

Practice Exam 4

1 10a

10b =

A 10a+bB 10a-bC 10a*bD 10a/b

2 10a x 10b =

A 10a+bB 10a-bC 10a*bD 10a/b

3 100 =

A 0B 1C 0.1D 10

4 Write 54,000,000 in scientific notation

A 5.4 x 107B 5.4 x 106C 5.4 x 108D 54 x 106

5 Write 0.0000350 in scientific notation

A 3.5 x 10-5B 3.5 x 10-4C 3.5 x 10-3D 3.5 x 10-6

6 Write 3,000,000 in scientific notation

A 3.0 x 105B 3.0 x 106C 30 x 106D 30 x 105

7 Write 35,000,000 in scientific notation

A 3.5 x 107B 35 x 107C 3.5 x 106D3.5 x 108

8 Write the number for 8.721 x 100

A 0B 1C 8.721D 87.21

9 Write the number for 9.570 x 10-2

A 0.0957B 957.0C 0.00957D 0.95700

10 Write the number for 3.5 x 10-4

A 0.03500B 0.00035C 0.000035D 0.0035

11 Write the number for (2.5 x 108) x (5.0 x 10–5)

A 12.5 x 103B 12.5 x 104C 1.25 x 104D 1.25 x 103

12 Calculate:1.44 x 107_

0.04 x 10–5

A 36 x 1012B 3.6 x 1012C 3.6 x 1013D 3.6 x 1011

13 Calculate:0.45 x 103 x 2.4 x 103 =

A 1.08 x 107B 1.08 x 106C 1.08 x 105D 1.08 x 104

14 A relationship between two or more quantities or amounts is:

A A formulaB A proportionC A functionD Don’t ask/tell

15 What exposure time would be required to produce 50mAs, if 400mA has been selected for a particular exposure? (mAs = mA * s)

A ½B ¼C 1/5D 1/8

16 What exposure time would be required to produce 80mAs, if 400mA has been selected for a particular exposure? (mAs = mA * s)

A ½B ¼C 1/5D 1/8

17 What is the total resistance (Rt) in a parallel circuit, if it contains three resistive elements having values of R1 = 4, R2 = 10, and R3 = 20 ohms?

(1 = 1 + 1 + 1 )

Rt R1 R2 R3

A 2½B 1/34C 34D 2/5

18 What is V equal to in terms of Q and C, if C = Q/V ?

A V=C/QB V=Q/CC V=CQ D V=QC

19 To create a proportion, you must have:

A a direct relationshipB two equivalent ratios

C an inverse relationshipC a fraction

20 What are the extremes in a:b::c:d ?

A a & bB a & cC a & dD b & c

21 What are the means in a =c ?

A a & bB a & cC a & dD b & c

For questions 22 and 23: The efficiency of a grid is also known as the grid ratio. Grid ratio is defined as the height of the lead strips divided by the distance between each lead strip. G = h/d

22 What is the grid ratio if a certain grid is made of 1/100 mm thick lead strips and is sandwiched between fiber interspaced material 3/10 mm thick and the height of the grid is 12/5 mm?

A 800:1B 1:8C 5:1D 8:1

23 What is the grid ratio if a certain grid is made of 1/100 mm thick lead strips and is sandwiched between fiber interspaced material 1/5 mm thick and the height of the grid is 1 mm?

A 500:1B 36:50C 5:1D 8:1

24 The product of the means is equal to:

A The sum of the exponents

B The product of the extremes

C The product of the denominators

D The square root of  times the radius

25 What is the principle of proportions?

A The more of one variable equals less of another variable

B The more of one variable equals more of another variable

C The product of the means is equal to the product of the extremes

D The product of the numerators is equal to the product of the denominators

26 What is the value of t equal to given the proportion,

9 = 3 ?

t 2

A 1.5B 13.5C 6D 8

27 What is the value of x equal to, given the proportion,

20 =2 ?

2x5

A 4B 25C 50D 87

28 What is the value of x in the proportion x:9 :: 5:15 ?

A 3B 9C 27D 81

29 If 1:75::5x:125x=

A 1/125B 1/5 C 1/3D ½

30 What is the value of x in the proportion,

x_ = 4 ?

2a a

A 4B 8C 8aD 8a2

31 “An increase in speed results in an increase in distance covered” and “A decrease in speed results in a decrease in distance covered” are examples of:

A Direct variationB Positive variation

C Indirect variationD Non-linear variation

32 In the expression y=kx what represents the proportionality constant?

A yB kC kxD x

33 Which formula shows direct variation?

A y=x/kB y=k/xC y=k/x2D y=kx

34 Which of the following factors would produce the greatest radiographic density? (See homework page 1.18/1.19 #21)

A 100mA, ¼ second, 36 inches SID

B 200mA, ½ second, 36 inches SID

C 50mA, 1 second, 36 inches SID

D 400mA, 1/20 second, 36 inches SID

35 Which of the following factors would produce the greatest radiographic density?

A 50mA, 1 second, 45 inches SID

B 100mA, ¼ second, 45 inches SID

C 120mA, 1/3 second, 45 inches SID

D 400mA, 1/20 second, 45 inches SID

36 Which of the following factors would produce the greatest radiographic density?

A 400mA, 3/40 second, 36 inches SID

B 200mA, 3/40 second, 36 inches SID

C 200mA, 15/100 second, 36 inches SID

D 400mA, 15/100 second, 36 inches SID

37 What will be the voltage in the secondary winding of the transformer, if there are 125 turns on the primary side of a transformer, 90,000 turns on the secondary side? The voltage supplied to the primary winding is equal to 110V. (See homework page 1.18/1.19 #22)

A 102,273B 12C 220D 79,200

INVERSE SQUARE LAW:

The change in beam intensity (amount of radiation that will cause exposure to the patient) and/or radiographic density (film blackening) varies inversely with the square of the

distance and is express in the following formula:

I1 = (d2)2

I2 (d1)2

Where:I1 = intensity at distance d1

I2 = intensity at distance d2

38 What would the new dosage to the patient be if the amount of radiation reaching a patient at 40in. is 3 R and the distance were increased to 60in.?

A 2B 1 1/3C 4½D 12

39 What relationship is illustrated by “An increase in one factor causes a decrease in another, or a decrease in one factor causes an increase in another”?

A Direct variationB Positive variation

C Inverse variationD Non-linear variation

40 Which formula shows inverse variation?

A y=kx2B y=k/xC y=xkD y=kx

41 “An increase in speed results in an decrease in time required” and “A decrease in speed results in an increase in time required” are examples of:

A Direct variationB Positive variation

C Inverse variationD Non-linear variation

42 What is the missing value if (x1, y1) and (x2, y2) are ordered pairs of an inverse variation problem and x1=3 y1=54 x2=2 and y2=?

A 36B 81C 0.11D 324

43 What is the missing value if (x1, y1) and (x2, y2) are ordered pairs of an inverse variation problem and x2=11.7 y1=19.5 y2=10.5 and x1=?

A 21.7B 6.3C 0.16D 324

44 What is the missing value if (x1, y1) and (x2, y2) are ordered pairs of an inverse variation problem and x1=2 y1=54 x2=3 and y2=?

A 36B 81C 0.11D 324

45 In the Cartesian Coordinate System, the origin can be described:

A The central axisB An graph before plotting

C The ordinateD The intersection of the x- and y- axis

46 The Cartesian Coordinate System can be described as:

A A plane with a number line

B A plane with two number lines

C A plane where two number lines intersect

D A plane where two number lines intersect at right angles

47 The horizontal axis is:

A x-axisB y-axisC Direct lineD Inverse line

48 Another name for the Cartesian Coordinate System is:

A Rectangular Coordinate SystemB Reticulated Coordinate System

C Rectal Coordinate SystemD Reptilian Coordinate System

49 The point (3,4) would be plotted from the origin as:

A 3 to the right on the x-axis, and 4 up on the y-axis

B 3 to the right on the y-axis, and 4 up on the x-axis

C 3 to the left on the x-axis, and 4 down on the y-axis

D 3 to the left on the y-axis, and 4 down on the x-axis

50 The point (-7,-3) would be plotted from the origin as:

A 7 to the right on the x-axis, and 3 up on the y-axis

B 7 to the right on the y-axis, and 3 up on the x-axis

C 7 to the left on the x-axis, and 3 down on the y-axis

D 7 to the left on the y-axis, and 3 down on the x-axis

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Key Practice Exam 4

Practice Exam 1.4

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10B

11C

12C

13B

14A

15D

16C

17A

18B

19B

20C

21D

22D

23C

24B

25C

26C

27B

28A

29C

30B

31A

32B

33D

34B

35A

36D

37D

38B

39C

40B

41C

42B

43B

44A

45D

46D

47A

48A

49A

50C

Practice Exam 1.4

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