Final Exam Solutions

1.3

35.  round 657,892 to the nearest thousand:  locate the digit to the right of the thousand:  657,892;  8 > 5 so replace it and all digits to the right with a 0 and add one to the thousands place.  658,000

36.  round 688,909 to the nearest thousand:  locate the digit to the right of the thousands:  688,909:  9 > 5 so replace it and all digits to the right with a 0 and add one to the thousands place  689.000

37.  locate the digit to the right of the thousands:  509,905:  9>5 so replace it and all digits to the right with a 0 and add one to the thousands place.  510,000

38.  locate the digit to the right of the thousands:  608,433: 4<5 so replace it and all digits to the right with a zero.  608,000

39.  locate the digit to the right of the thousands:  3,789,345: 3<5 so replace it and all digits to the right with a zero.  3,789,000

40.  locate the digit to the right of the thousands:  5,744,500:  5 is greater than or equal to 5 so replace it and all digits to the right with a 0 and add one to the thousands place.  5,745,000

1.7    “*” means to multiply

46.  4*9+5*8

36+40

=76

47.  8*100-6*64

800-384

=416

48.  5*121-3*8

605-24

=581

49.  2(3+6*5)

2(3+30)

2(33)

=66

50.  8(1+8)

8(9)

=72

59.  (4)(10)

=40

60.  (4)(14)

=56

61.  3(7)+4(5)

21+20

=41

66.  3(16)+10÷5

48+10÷5

48+2

=50

67.  8*16+25÷5-9

128+5-9

133-9

=124

68..  5*81+16÷8-4

405+2-4

=403

74.  20+12   =  32    =  8

      11-7          4

2.5

39.  -42+(-6)

         20-4

=  -48

    16

= -3

40.  -72+(-5)

         12-1

= -77

    11

= -7

41. 84

     -12

= -7

42.  64

       4

= 16

2.6

29.  = 7*x + 7*5

=7x+35

30.  8*x+8*3

=8x+24

31.  6*a – 6*7

=6a – 42

32.  4*a – 4*9

= 4a – 36

33.  2*x – 2*y

= 2x – 2y

34.  5*x – 5*a

= 5x – 5a

35.  4*5+4*x

= 20+4x

3.5

33. 

12 = 2*2*3

8 = 2*2*2   LCD = 2*2*2*3=24

5*2 = 3*3

12*2  8*3

10  + 9

24    24

=19

  24

34. 

16= 2*2*2*2

12= 2*2*3   LCD = 2*2*2*2*3 = 48

9*3   +  7*4

16*3     12*4

27   + 28

48      48

= 55

  48

35. 

20= 2*2*5

30= 2*3*5  LCD = 2*2*3*5 = 60

-1*3 + 8*2

20*3   30*2

= -3 + 16

  60     60

= 13

   60

41. 

30= 2*3*5

42 = 2*3*7  LCD = 2*3*5*7 = 210

17*7 + 11*5

30*7    42*5

119 + 55

210    210

= 174

  210

= 29

  35

43. 

84 = 2*2*3*7

90 = 2*3*3*5  LCD = 2*2*3*3*5*7 = 1260

25*15 + 41*14

84*15     90*14

375 + 574

1260  1260

=949

1260

55.

10= 2*5

5=5

20=2*2*5  LCD = 2*2*5

1*2 + 4*4 - 3

10*2  5*4   20

= 2 + 16 - 3

  20   20   20

18 - 3

20   20

= 15

  20

= 3

  4

56.

2=2

4=2*2

8=2*2*2  LCD = 2*2*2=8

1*4 + 3*2 - 5

2*4    4*2    8

4 + 6 - 5

8    8   8

=5

  8