Lesson 3 - Decimal Quiz - Quiz & Trivia

1) Calculate to 2 decimal places2.11432 + 2.220124

2.22

4.33

3.22

2.45

The correct answer is 4.33 because when we add 2.11432 and 2.220124 together and round to two decimal places, we get 4.33.

Explanation

The correct answer is 4.33 because when we add 2.11432 and 2.220124 together and round to two decimal places, we get 4.33.

2) Which number correctly shows Pi expressed to 4 dp?

3.1429

3.14

3.1

3.14285

The number 3.1429 correctly shows Pi expressed to 4 decimal places. Pi is an irrational number with an infinite number of decimal places, but when rounded to 4 decimal places, it becomes 3.1429.

Explanation

The number 3.1429 correctly shows Pi expressed to 4 decimal places. Pi is an irrational number with an infinite number of decimal places, but when rounded to 4 decimal places, it becomes 3.1429.

3) Calculate to 2 decimal places1.22222 + 1.333333

2.55

2.22

3.22

1.23

The given question asks to calculate the sum of 1.22222 and 1.333333 to 2 decimal places. When we add these two numbers, we get 2.555553. However, since we need to round the answer to 2 decimal places, we round it to 2.56. Therefore, the correct answer is 2.56.

Explanation

The given question asks to calculate the sum of 1.22222 and 1.333333 to 2 decimal places. When we add these two numbers, we get 2.555553. However, since we need to round the answer to 2 decimal places, we round it to 2.56. Therefore, the correct answer is 2.56.

4) Calculate to 2 decimal places2.89 + 0.10

0.89

3.22

2.99

5.1

When we add 2.89 and 0.10, we get a sum of 2.99.

Explanation

When we add 2.89 and 0.10, we get a sum of 2.99.

5) Which number correctly shows 98.9995 to 2 dp?

99.00

98.99

98.999

98.100

The number 98.9995 rounded to 2 decimal places is 99.00. This is because when rounding to 2 decimal places, we look at the third decimal place. If it is 5 or greater, we round up the second decimal place. In this case, the third decimal place is 9, so we round up the second decimal place from 9 to 0, resulting in 99.00.

Explanation

The number 98.9995 rounded to 2 decimal places is 99.00. This is because when rounding to 2 decimal places, we look at the third decimal place. If it is 5 or greater, we round up the second decimal place. In this case, the third decimal place is 9, so we round up the second decimal place from 9 to 0, resulting in 99.00.

6) Which correctly shows 32.459 to 1 dp?

32.5

32.46

32.45

32.459

The correct answer is 32.5 because rounding 32.459 to 1 decimal place means that we only consider the first decimal digit after the decimal point. Since the digit 5 is greater than or equal to 5, we round up the previous digit, which is 2, to 3. Therefore, the number becomes 32.5.

Explanation

The correct answer is 32.5 because rounding 32.459 to 1 decimal place means that we only consider the first decimal digit after the decimal point. Since the digit 5 is greater than or equal to 5, we round up the previous digit, which is 2, to 3. Therefore, the number becomes 32.5.

7) Round to 1 decimal place0.33 + 0.23

0.6

1.5

2.33

1.45

The given question asks to round the sum of 0.33 and 0.23 to 1 decimal place. Adding 0.33 and 0.23 gives a sum of 0.56. When rounding to 1 decimal place, we look at the digit in the second decimal place, which is 6. Since 6 is greater than or equal to 5, we round up the first decimal place, resulting in the answer of 0.6.

Explanation

The given question asks to round the sum of 0.33 and 0.23 to 1 decimal place. Adding 0.33 and 0.23 gives a sum of 0.56. When rounding to 1 decimal place, we look at the digit in the second decimal place, which is 6. Since 6 is greater than or equal to 5, we round up the first decimal place, resulting in the answer of 0.6.

8) Calculate to 1 decimal place0.49 + 0.29995

0.6

0.8

0.89

3.44

The correct answer is 0.8 because when we add 0.49 and 0.29995, we get a sum of 0.78995. Rounding this to one decimal place gives us 0.8.

Explanation

The correct answer is 0.8 because when we add 0.49 and 0.29995, we get a sum of 0.78995. Rounding this to one decimal place gives us 0.8.

9) Calculate to 3 decimal places 5.44678

5.447

5.55

5.467

5.446

The given question asks to calculate 5.44678 to 3 decimal places. To do this, we look at the fourth decimal place, which is 6. Since 6 is greater than or equal to 5, we round up the third decimal place, which is 4, to 5. Therefore, the correct answer is 5.447.

Explanation

The given question asks to calculate 5.44678 to 3 decimal places. To do this, we look at the fourth decimal place, which is 6. Since 6 is greater than or equal to 5, we round up the third decimal place, which is 4, to 5. Therefore, the correct answer is 5.447.

10) Which numbers shows 8.991253 to 4 dp?

8.9913

8.9912

8.9915

8.9910

The question asks for the number that represents 8.991253 to 4 decimal places. To round to 4 decimal places, we look at the fifth decimal place (3 in this case). If the fifth decimal place is 5 or greater, we round up the fourth decimal place. Since the fifth decimal place is 3, which is less than 5, we do not round up. Therefore, the correct answer is 8.9913.

Explanation

The question asks for the number that represents 8.991253 to 4 decimal places. To round to 4 decimal places, we look at the fifth decimal place (3 in this case). If the fifth decimal place is 5 or greater, we round up the fourth decimal place. Since the fifth decimal place is 3, which is less than 5, we do not round up. Therefore, the correct answer is 8.9913.