Question

there are 27 pennies on one pan of a pan balance and 18 pennies on the other. to make the pans balance, skyler thinks 5 pennies should be added to the higher pan. frankie thinks 8 pennies should be added, and robin thinks 9 pennies should be added. use the equation 27 = 18 + p to determine who is correct.

Explanation:

Step1: Solve the equation for \( p \)

We have the equation \( 27 = 18 + p \). To solve for \( p \), we subtract 18 from both sides of the equation.

$$ 27 - 18 = 18 + p - 18 $$

Step2: Calculate the value of \( p \)

Simplifying the left side: \( 27 - 18 = 9 \), and the right side simplifies to \( p \). So \( p = 9 \).

Answer:

Robin is correct because when we solve the equation \( 27 = 18 + p \), we find that \( p = 9 \), which matches Robin's thought that 9 pennies should be added.