Practice30Create account

Ravi simplifies and writes the answer as . What is wrong with his answer?

Class 7Rational NumbersRational Numbers
  • ANothing is wrong — is already the standard form
  • BHe should have divided by 3, giving
  • CThe answer should be , because two minus signs keep the number negative
  • DStandard form needs a POSITIVE denominator, so the answer must be

Step-by-Step Solution

Ravi's cancelling is right (GCD = 6), but standard form has two conditions: lowest terms AND a positive denominator. . The tempting wrong answer keeps one minus sign, but two minus signs cancel — they do not leave the number negative.
Answer: D) Standard form needs a POSITIVE denominator, so the answer must be

Key idea: Standard form (simplest form)

To put a rational number in standard form:

1. If the denominator is negative, multiply both top and bottom by −1 to make it positive.
2. Divide top and bottom by their GCD.

Example: −12/−18. Make denominator positive: 12/18. GCD = 6. Divide: 2/3.

Example: 15/−20. Make denominator positive: −15/20. GCD = 5. Divide: −3/4.

Master this chapter in 30 minutes a day.

Don't just memorise the answer — build a daily practice habit.

Practice 5 Similar Questions Free →

All Rational Numbers practice questions

More Class 7 Rational Numbers practice

Which of these rational numbers is ALREADY in standard form?The standard form of -42/56 is p/q. What is the value of p + q?-45/60 is to be reduced to standard form in ONE step. By which number must both the…Which list contains ONLY rational numbers equal to -2/7?Do 4/-7 and -12/21 name the same rational number?