Question on contracts calculation (forex futures hedging)

Hi

I hope someone can help, this may seem basic but i’m seeing conflicting methods within my Kaplan study text/exam kit!!

When calculating the number of contracts for a forex future hedge, if the contract currency is different to the currency you are hedging, do you convert the hedging amount at the futures rate or the lockin rate?? I’m seeing both in my Kaplan books so im very confused!

EG

Your are based in EUR and will be receiving $18.2m on 31st Aug

Sep futures of 1.1422 are available, contract size EUR 200,000

Spot rate 1.1485

So, as selling $ and buying EUR, you will buy Sep futures.

number of contracts = 18.2m / rate / 200,000. Which rate, lockin or futures?

In addition, when calculating the remainder (if calculation doesn’t give a whole contract number) to hedge using a forward rate, again, should lockin or futures rate be used to calculate remainder?

EG

$18.2m – (contract number x 200,000 x rate)

Thank you