diff --git a/EventMixing/src/Mu2eProductMixer.cc b/EventMixing/src/Mu2eProductMixer.cc
index 620f96f859..6edf1d18fc 100644
--- a/EventMixing/src/Mu2eProductMixer.cc
+++ b/EventMixing/src/Mu2eProductMixer.cc
@@ -236,7 +236,7 @@ namespace mu2e {
     }
     if (mixCosmicLivetimes_) {
       if(generatedEvents_ == 0)throw cet::exception("BADINPUT")<<"Mu2eProductMixer: generated event count =0; was the mixin file opened correctly?" << std::endl;
-      float scaling = resampledEvents_ / generatedEvents_;
+      float scaling = static_cast<float>(resampledEvents_) / static_cast<float>(generatedEvents_);
       auto livetime = std::make_unique<CosmicLivetime>(totalPrimaries_ * scaling,
                                                        area_, lowE_, highE_, fluxConstant_, livetime_ * scaling);
       sr.put(std::move(livetime), subrunLivetimeInstanceName_, art::fullSubRun());