Calculate the multiplier resistance

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Homework Statement
Find the multiplier resistance
Relevant Equations
Rm = V/i – Rc
Question:

Printed text problem: A moving coil ammeter gives a full scale deflection for a current i = 250 mA and its coil has a resistance Rc = 0.75 Ω. It is provided with a multiplier resistance Rm that allows a voltage measurement of up to 5 V. What is the value of the multiplier resistance?

My attempt:

Handwritten working: Rm = V/i - Rc, then V = 5, i = 250 mA, Rc = 0.75 ohm, Rm = 5/(250x10^-3) - 0.75 = 19.25 ohm.


So the resistance of the multiplier resistance comes out to be 19.25 ohms?