Tag: science & technology

Quizzes (551) Questions (11015)

Questions Related to science & technology

Multiple choice general knowledge science & technology

The probability that an electronic device produced by a company does not function properly is equal to 0.1. If 10 devices are bought, then the probability, to the nearest thousandth, that 7 devices function properly is

  1. 0.057

  2. 0.478

  3. 0.001

  4. 0
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

This is a binomial probability problem. The probability of a device functioning properly is 1 - 0.1 = 0.9. We need exactly 7 functioning devices out of 10, which follows the binomial formula: C(10,7) × (0.9)^7 × (0.1)^3. Calculating: 120 × 0.4783 × 0.001 ≈ 0.057.

Multiple choice general knowledge science & technology

When a metallic ball bearing is placed inside a cylindrical container, of radius 2 cm, the height of the water, inside the container, increases by 0.6 cm. The radius, to the nearest tenth of a centimeter, of the ball bearing is

  1. 1 cm

  2. 1.2 cm

  3. 2 cm

  4. 0.6 cm
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The ball displaces water equal to its volume. Ball volume = (4/3)πr³. Displaced water volume = π(2)²(0.6) = 2.4π. Equating: (4/3)πr³ = 2.4π, which gives r³ = 1.8 and r ≈ 1.2 cm.

Multiple choice general knowledge science & technology

The exam scores of all 500 students were recorded and it was determined that these scores were normally distributed. If Jane's score is 0.8 standard deviation above the mean, then how many, to the nearest unit, students scored above Jane?

  1. 394

  2. 250

  3. 400

  4. 106
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A score 0.8 standard deviations above the mean corresponds to the 78.81st percentile. Therefore, about 21.19% of students scored above Jane. For 500 students: 500 × 0.2119 ≈ 106 students.

Multiple choice general knowledge science & technology

Five different books (A, B, C, D and E) are to be arranged on a shelf. Books C and D are to be arranged first and second starting from the right of the shelf. The number of different orders in which books A, B and E may be arranged is

  1. 5!

  2. 3!

  3. 2! * 3!

  4. 2!
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Books C and D are fixed at specific positions from the right. The remaining 3 books (A, B, E) can be arranged in any order among themselves. The number of permutations of 3 items is 3! = 6.

Multiple choice general knowledge science & technology

Five different books (A, B, C, D and E) are to be arranged on a shelf. Books C and D are to be arranged first and second starting from the right of the shelf. The number of different orders in which books A, B and E may be arranged is

  1. 5!

  2. 3!

  3. 2! * 3!

  4. 2!
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Books C and D are fixed at specific positions from the right. The remaining 3 books (A, B, E) can be arranged in any order among themselves. The number of permutations of 3 items is 3! = 6.

Multiple choice general knowledge science & technology

The three solutions of the equation f(x) = 0 are -2, 0, and 3. Therefore, the three solutions of the equation f(x - 2) = 0 are
    • 4, -2, and 1

  2. -2, 0 and 3

  3. 4, 2, and 5

  4. 0, 2 and 5
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

If f(x) = 0 has solutions at -2, 0, and 3, then for f(x - 2) = 0, we substitute x - 2 for x. This means x - 2 = -2, 0, or 3, giving x = 0, 2, and 5. The transformation shifts all solutions 2 units to the right.