If (R(t)=b-6t) and (R(5)=50), what is (b)?
Answer and explanation
Correct answer: 80
Given \(R(t)=b-6t\). Substituting \(t=5\) gives \(R(5)=b-6(5)=b-30\). Since \(R(5)=50\), \(b-30=50\), so \(b=80\). Option 50 is the value of \(R(5)\), not the value of \(b\). Exam tip: When a function value is given, first substitute the stated input into the formula and form an equation.
Frequently asked questions
What is the correct answer to this question?
80
Why is this the correct answer?
Given \(R(t)=b-6t\). Substituting \(t=5\) gives \(R(5)=b-6(5)=b-30\). Since \(R(5)=50\), \(b-30=50\), so \(b=80\). Option 50 is the value of \(R(5)\), not the value of \(b\). Exam tip: When a function value is given, first substitute the stated input into the formula and form an equation.
Which subject and chapter does this question cover?
This is a Class 9 Mathematics question. Chapter: Introduction to Polynomials. Topic: Linear growth and decay.
Student feedback
Was this question useful?
👍 0 Helpful 👎 0 Not helpful
Yes 0% No 0%
0 responsesStudent Reviews
No published reviews yet.
