Rates And Ratios Pretest

Explanation
To convert kilometers to meters, you need to multiply the value by 1000. In this case, 3.6 kilometers multiplied by 1000 equals 3600 meters. Therefore, the correct answer is 3600m.

Explanation
The given statement is false. To convert a mixed number to an improper fraction, we multiply the whole number by the denominator of the fraction and add the numerator. In this case, 2 multiplied by 7 is 14, and adding 1 gives us 15. So, 2 1/7 as an improper fraction is 15/7, not 23/7.

Explanation
The number 0.52517, when rounded to 2 decimal places, would be 0.53. This is because the digit in the third decimal place, 5, is greater than or equal to 5, so it causes the digit in the second decimal place, 2, to be rounded up to 3.

Explanation
The given expression can be simplified by dividing both the numerator and denominator by their greatest common divisor, which in this case is 12. Simplifying each fraction step by step, we get 36/48 = 3/4. Therefore, the answer is 3/4.

Explanation
To convert mm to cm, we need to divide the value in mm by 10. In this case, we have 2000mm, so dividing it by 10 gives us 200cm. Therefore, the correct answer is 200cm.

Explanation
When rounding a number to 2 decimal places, we look at the digit in the third decimal place. If this digit is 5 or greater, we round up the second decimal place, and if it is less than 5, we leave the second decimal place as it is. In this case, the digit in the third decimal place is 9, which is greater than 5. Therefore, we round up the second decimal place to 0, resulting in 3.90. Additionally, 3.9 is also a valid answer as it is the rounded version of 3.899 to 1 decimal place.

Explanation
The given equation states that the fraction 2/3 is equal to 8 divided by x. To find the value of x, we can cross multiply. By multiplying 2 and x, we get 2x, and by multiplying 3 and 8, we get 24. Therefore, the equation becomes 2x = 24. To isolate x, we divide both sides of the equation by 2, resulting in x = 12. Hence, the value of x is 12.

Explanation
The equation x/2 = 21/6 can be simplified by multiplying both sides by 2, resulting in x = 21/3. Simplifying further, we find that x equals 7.

Explanation
To find 30% of a number, we multiply the number by 0.30. In this case, 30% of 150 is calculated as 150 * 0.30 = 45. Therefore, the answer is 45.