From 7b69ed15acf0dc8547dd43926e857dececb84f9c Mon Sep 17 00:00:00 2001
From: Vito <5780819+Tapanito@users.noreply.github.com>
Date: Wed, 19 Nov 2025 10:44:01 +0100
Subject: [PATCH] documents why multiplication is performed first

---
 src/xrpld/app/misc/detail/LendingHelpers.cpp | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/xrpld/app/misc/detail/LendingHelpers.cpp b/src/xrpld/app/misc/detail/LendingHelpers.cpp
index 13664b5b89..78c23f9a80 100644
--- a/src/xrpld/app/misc/detail/LendingHelpers.cpp
+++ b/src/xrpld/app/misc/detail/LendingHelpers.cpp
@@ -252,8 +252,11 @@ loanAccruedInterest(
     auto const secondsSinceLastPayment =
         parentCloseTime.time_since_epoch().count() - lastPaymentDate;
 
-    return principalOutstanding * periodicRate *
-        (secondsSinceLastPayment / paymentInterval);
+    // Division is more likely to introduce rounding errors, which will then get
+    // amplified by multiplication. Therefore, we first multiply, and only then
+    // divide.
+    return principalOutstanding * periodicRate * secondsSinceLastPayment /
+        paymentInterval;
 }
 
 /* Applies a payment to the loan state and returns the breakdown of amounts