Expresswala Academy Mathematics Tuition

Simple Equations using Integers

MCQ test, Set 9

  • Set 9 of 10
  • 25 questions
  • 25 marks
  • 30 minutes

Download the PDF (with key sheet and solutions, 73.4 KB)

Choose one answer for each question, then check your score at the end. Each correct answer carries 1 mark; there is no negative marking.

  1. If x+15=−12x + 15 = -12, then x=x =
    Answer and solution

    Answer: (B) −27-27

    x+15=−12x + 15 = -12

    ⇒x=−12−15\Rightarrow x = -12 - 15

    ⇒x=−27\Rightarrow x = -27

  2. The solution of x+76=32x + 76 = 32 is
    Answer and solution

    Answer: (C) −44-44

    x+76=32x + 76 = 32

    ⇒x=32−76\Rightarrow x = 32 - 76

    ⇒x=−44\Rightarrow x = -44

  3. Solve x−31=−60x - 31 = -60. Then x=x =
    Answer and solution

    Answer: (D) −29-29

    x−31=−60x - 31 = -60

    ⇒x=−60+31\Rightarrow x = -60 + 31

    ⇒x=−29\Rightarrow x = -29

  4. If x−5=85x - 5 = 85, then x=x =
    Answer and solution

    Answer: (B) 9090

    x−5=85x - 5 = 85

    ⇒x=85+5\Rightarrow x = 85 + 5

    ⇒x=90\Rightarrow x = 90

  5. If x×2=22x \times 2 = 22, then x=x =
    Answer and solution

    Answer: (B) 1111

    x×2=22x \times 2 = 22

    ⇒x=222\displaystyle \Rightarrow x = \frac{22}{2}

    ⇒x=11\Rightarrow x = 11

  6. The solution of x9=120\displaystyle \frac{x}{9} = 120 is
    Answer and solution

    Answer: (A) 10801080

    x9=120\displaystyle \frac{x}{9} = 120

    ⇒x=120×9\Rightarrow x = 120 \times 9

    ⇒x=1080\Rightarrow x = 1080

  7. Which of the following equations has the solution x=64x = 64?
    Answer and solution

    Answer: (D) x+9=73x + 9 = 73

    Solve each one:

    x+9=73⇒x=73−9=64x + 9 = 73 \Rightarrow x = 73 - 9 = 64

    x−9=73⇒x=73+9=82x - 9 = 73 \Rightarrow x = 73 + 9 = 82

    x+9=−73⇒x=−73−9=−82x + 9 = -73 \Rightarrow x = -73 - 9 = -82

    x−9=−73⇒x=−73+9=−64x - 9 = -73 \Rightarrow x = -73 + 9 = -64

    Only x+9=73x + 9 = 73 gives x=64x = 64.

  8. Which of the following equations has the solution x=1053x = 1053?
    Answer and solution

    Answer: (C) x9=117\displaystyle \frac{x}{9} = 117

    Solve each one:

    x+9=117⇒x=117−9=108x + 9 = 117 \Rightarrow x = 117 - 9 = 108

    x−9=117⇒x=117+9=126x - 9 = 117 \Rightarrow x = 117 + 9 = 126

    x×9=117⇒x=1179=13\displaystyle x \times 9 = 117 \Rightarrow x = \frac{117}{9} = 13

    x9=117⇒x=117×9=1053\displaystyle \frac{x}{9} = 117 \Rightarrow x = 117 \times 9 = 1053

    Only x9=117\displaystyle \frac{x}{9} = 117 gives x=1053x = 1053.

  9. Solve x−286=−594x - 286 = -594. Then x=x =
    Answer and solution

    Answer: (B) −308-308

    x−286=−594x - 286 = -594

    ⇒x=−594+286\Rightarrow x = -594 + 286

    Column subtraction: 594−286=308594 - 286 = 308; the bigger number is negative, so xx is negative

    ⇒x=−308\Rightarrow x = -308

  10. If x×35=101535x \times 35 = 101535, then x=x =
    Answer and solution

    Answer: (D) 29012901

    x×35=101535x \times 35 = 101535

    ⇒x=10153535\displaystyle \Rightarrow x = \frac{101535}{35}

    Long division: 101÷35=2101 \div 35 = 2, remainder 3131; 315÷35=9315 \div 35 = 9, remainder 00; 3÷35=03 \div 35 = 0, remainder 33; 35÷35=135 \div 35 = 1, remainder 00

    ⇒x=2901\Rightarrow x = 2901

  11. If x−4=87\displaystyle \frac{x}{-4} = 87, then x=x =
    Answer and solution

    Answer: (A) −348-348

    x−4=87\displaystyle \frac{x}{-4} = 87

    ⇒x=87×(−4)\Rightarrow x = 87 \times (-4)

    +×−=−+ \times - = -

    ⇒x=−348\Rightarrow x = -348

  12. If x10=−163\displaystyle \frac{x}{10} = -163, then x=x =
    Answer and solution

    Answer: (B) −1630-1630

    x10=−163\displaystyle \frac{x}{10} = -163

    ⇒x=(−163)×10\Rightarrow x = (-163) \times 10

    −×+=−- \times + = -

    ⇒x=−1630\Rightarrow x = -1630

  13. The solution of 5x+111=−595x + 111 = -59 is
    Answer and solution

    Answer: (C) −34-34

    5x+111=−595x + 111 = -59

    ⇒5x=−59−111\Rightarrow 5x = -59 - 111

    ⇒5x=−170\Rightarrow 5x = -170

    ⇒x=−1705\displaystyle \Rightarrow x = \frac{-170}{5}

    ⇒x=−34\Rightarrow x = -34

  14. The solution of 9x−52=1469x - 52 = 146 is
    Answer and solution

    Answer: (D) 2222

    9x−52=1469x - 52 = 146

    ⇒9x=146+52\Rightarrow 9x = 146 + 52

    ⇒9x=198\Rightarrow 9x = 198

    ⇒x=1989\displaystyle \Rightarrow x = \frac{198}{9}

    ⇒x=22\Rightarrow x = 22

  15. If x2+52=77\displaystyle \frac{x}{2} + 52 = 77, then x=x =
    Answer and solution

    Answer: (B) 5050

    x2+52=77\displaystyle \frac{x}{2} + 52 = 77

    ⇒x2=77−52\displaystyle \Rightarrow \frac{x}{2} = 77 - 52

    ⇒x2=25\displaystyle \Rightarrow \frac{x}{2} = 25

    ⇒x=25×2\Rightarrow x = 25 \times 2

    ⇒x=50\Rightarrow x = 50

  16. The solution of 8x3+5=−19\displaystyle \frac{8x}{3} + 5 = -19 is
    Answer and solution

    Answer: (A) −9-9

    8x3+5=−19\displaystyle \frac{8x}{3} + 5 = -19

    ⇒8x3=−19−5\displaystyle \Rightarrow \frac{8x}{3} = -19 - 5

    ⇒8x3=−24\displaystyle \Rightarrow \frac{8x}{3} = -24

    ⇒8x=−24×3\Rightarrow 8x = -24 \times 3

    ⇒8x=−72\Rightarrow 8x = -72

    ⇒x=−728\displaystyle \Rightarrow x = \frac{-72}{8}

    ⇒x=−9\Rightarrow x = -9

  17. The solution of 4x9−6=38\displaystyle \frac{4x}{9} - 6 = 38 is
    Answer and solution

    Answer: (C) 9999

    4x9−6=38\displaystyle \frac{4x}{9} - 6 = 38

    ⇒4x9=38+6\displaystyle \Rightarrow \frac{4x}{9} = 38 + 6

    ⇒4x9=44\displaystyle \Rightarrow \frac{4x}{9} = 44

    ⇒4x=44×9\Rightarrow 4x = 44 \times 9

    ⇒4x=396\Rightarrow 4x = 396

    ⇒x=3964\displaystyle \Rightarrow x = \frac{396}{4}

    ⇒x=99\Rightarrow x = 99

  18. If 8x+13=27−6x8x + 13 = 27 - 6x, then x=x =
    Answer and solution

    Answer: (A) 11

    8x+13=27−6x8x + 13 = 27 - 6x

    ⇒8x+6x=27−13\Rightarrow 8x + 6x = 27 - 13

    ⇒14x=14\Rightarrow 14x = 14

    ⇒x=1414\displaystyle \Rightarrow x = \frac{14}{14}

    ⇒x=1\Rightarrow x = 1

  19. The solution of 3x+15+4x=19+5x3x + 15 + 4x = 19 + 5x is
    Answer and solution

    Answer: (C) 22

    3x+15+4x=19+5x3x + 15 + 4x = 19 + 5x

    ⇒7x+15=19+5x\Rightarrow 7x + 15 = 19 + 5x

    ⇒7x−5x=19−15\Rightarrow 7x - 5x = 19 - 15

    ⇒2x=4\Rightarrow 2x = 4

    ⇒x=42\displaystyle \Rightarrow x = \frac{4}{2}

    ⇒x=2\Rightarrow x = 2

  20. Solve 6x−103=−49+8x6x - 103 = -49 + 8x. Then x=x =
    Answer and solution

    Answer: (B) −27-27

    6x−103=−49+8x6x - 103 = -49 + 8x

    ⇒6x−8x=−49+103\Rightarrow 6x - 8x = -49 + 103

    ⇒−2x=54\Rightarrow -2x = 54

    ⇒x=54−2\displaystyle \Rightarrow x = \frac{54}{-2}

    (+÷−=−)(+ \div - = -)

    ⇒x=−27\Rightarrow x = -27

  21. If −14x−13−4x=−175-14x - 13 - 4x = -175, then x=x =
    Answer and solution

    Answer: (A) 99

    −14x−13−4x=−175-14x - 13 - 4x = -175

    ⇒−18x−13=−175\Rightarrow -18x - 13 = -175

    ⇒−18x=−175+13\Rightarrow -18x = -175 + 13

    ⇒−18x=−162\Rightarrow -18x = -162

    ⇒x=−162−18\displaystyle \Rightarrow x = \frac{-162}{-18}

    (−÷−=+)(- \div - = +)

    ⇒x=9\Rightarrow x = 9

  22. The sum of two integers is −910-910. If one of them is 649649, the other is
    Answer and solution

    Answer: (C) −1559-1559

    Let the other integer be xx.

    x+649=−910x + 649 = -910

    ⇒x=−910−649\Rightarrow x = -910 - 649

    ⇒x=−1559\Rightarrow x = -1559

  23. What number should be added to −170-170 to get −284-284?
    Answer and solution

    Answer: (A) −114-114

    Let the number be xx.

    −170+x=−284-170 + x = -284

    ⇒x=−284−(−170)\Rightarrow x = -284 - (-170)

    ⇒x=−284+170\Rightarrow x = -284 + 170

    ⇒x=−114\Rightarrow x = -114

  24. What number should be subtracted from 144144 to get 115115?
    Answer and solution

    Answer: (D) 2929

    Let the number be xx.

    144−x=115144 - x = 115

    ⇒−x=115−144\Rightarrow -x = 115 - 144

    ⇒−x=−29\Rightarrow -x = -29

    ⇒x=29\Rightarrow x = 29

  25. The product of two integers is −255-255. If one of them is 1515, the other is
    Answer and solution

    Answer: (D) −17-17

    Let the other integer be xx.

    x×15=−255x \times 15 = -255

    ⇒x=−25515\displaystyle \Rightarrow x = \frac{-255}{15}

    Long division: 25÷15=125 \div 15 = 1, remainder 1010; 105÷15=7105 \div 15 = 7, remainder 00

    (−÷+=−)(- \div + = -)

    ⇒x=−17\Rightarrow x = -17