diff --git a/packages/scratch-vm/src/blocks/scratch3_operators.js b/packages/scratch-vm/src/blocks/scratch3_operators.js
index cb5d6ef84fd..8fc4a7c6158 100644
--- a/packages/scratch-vm/src/blocks/scratch3_operators.js
+++ b/packages/scratch-vm/src/blocks/scratch3_operators.js
@@ -136,8 +136,8 @@ class Scratch3OperatorsBlocks {
         case 'floor': return Math.floor(n);
         case 'ceiling': return Math.ceil(n);
         case 'sqrt': return Math.sqrt(n);
-        case 'sin': return parseFloat(Math.sin((Math.PI * n) / 180).toFixed(10));
-        case 'cos': return parseFloat(Math.cos((Math.PI * n) / 180).toFixed(10));
+        case 'sin': return Math.round(Math.sin((Math.PI * (n % 360)) / 180) * 1e10) / 1e10;
+        case 'cos': return Math.round(Math.cos((Math.PI * (n % 360)) / 180) * 1e10) / 1e10;
         case 'tan': return MathUtil.tan(n);
         case 'asin': return (Math.asin(n) * 180) / Math.PI;
         case 'acos': return (Math.acos(n) * 180) / Math.PI;
diff --git a/packages/scratch-vm/src/util/cast.js b/packages/scratch-vm/src/util/cast.js
index af624a30fa0..8c9a93164f7 100644
--- a/packages/scratch-vm/src/util/cast.js
+++ b/packages/scratch-vm/src/util/cast.js
@@ -161,7 +161,7 @@ class Cast {
                 return true;
             }
             // True if it's "round" (e.g., 2.0 and 2).
-            return val === parseInt(val, 10);
+            return val % 1 === 0;
         } else if (typeof val === 'boolean') {
             // `True` and `false` always represent integer after Scratch cast.
             return true;
diff --git a/packages/scratch-vm/src/util/math-util.js b/packages/scratch-vm/src/util/math-util.js
index f9a1a75ec93..1b23cb6b7d9 100644
--- a/packages/scratch-vm/src/util/math-util.js
+++ b/packages/scratch-vm/src/util/math-util.js
@@ -60,7 +60,7 @@ class MathUtil {
         case 270:
             return -Infinity;
         default:
-            return parseFloat(Math.tan((Math.PI * angle) / 180).toFixed(10));
+            return Math.round(Math.tan((Math.PI * angle) / 180) * 1e10) / 1e10;
         }
     }