All topics

Real numbers

number sets and set operations, intervals, equations with absolute value, divisibility and remainders, powers with integer and rational exponents, roots of any degree, logarithms, compound interest

Exercises are drawn at random from a large bank - every click gives a different set.

Solved: 0 of 10

1

Find A ∩ B

A = {−4, 7, 12, 13} B = {−4, 6, 12}

2

Problem

The value of an investment grew every year by the same percentage. At the start it was 32 000 zloty, and after 3 years it was 55 296 zloty. By what percentage did it grow each year?

3

How many solutions does the equation have?

|x + 7| = 6

4

Problem

110 000 zloty was deposited at 3% a year, compounded annually. How many zloty will be in the account after 3 years?

5

Calculate

log₁₀ 100⁵

6

Problem

44 000 zloty was put on deposit for 1 year. The interest rate is 6% a year, compounded half-yearly. Ignore the tax on interest. How many zloty will be on the deposit after that time? Give the answer to the nearest grosz.

7

Rationalise the denominator

19/(2√3)

8

Write the interval shown on the number line

Which interval is marked on the number line?

A number line with a scale in steps of 1; an interval of numbers is marked on it.−9−8−7−6−5−4−3−2−10123
9

Problem

A natural number n leaves a remainder of 1 when divided by 3. What remainder does 5n² leave when divided by 3?

10

List the elements of the set (here ℕ = {0, 1, 2, …})

A = {x ∈ ℕ : x < 0}

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Real numbers - exercises with solutions | PhiBoard