If (A(t)=170-9t) and (B(t)=38+4t), when will (A(t)) be (2) more than (B(t))?
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Answer and explanation
Correct answer: \(t=10\)
“2 more than \(B(t)\)” means \(A(t)=B(t)+2\). So, \(170-9t=38+4t+2\), which gives \(170-9t=40+4t\) and \(130=13t\). Hence, \(t=10\). At \(t=9\), the difference is 15, not 2. Exam tip: In comparison questions, first convert the stated difference into an equation.
Frequently asked questions
What is the correct answer to this question?
\(t=10\)
Why is this the correct answer?
“2 more than \(B(t)\)” means \(A(t)=B(t)+2\). So, \(170-9t=38+4t+2\), which gives \(170-9t=40+4t\) and \(130=13t\). Hence, \(t=10\). At \(t=9\), the difference is 15, not 2. Exam tip: In comparison questions, first convert the stated difference into 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.
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