solution to 3.44

diff --git a/src/sicp/ex3_44.rkt b/src/sicp/ex3_44.rkt
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+#lang racket
+
+;; Consider the problem of transferring an amount from one account to
+;; another. Ben Bitdiddle claims that this can be accomplished with the
+;; following procedure, even if there are multiple people concurrently 
+;; transferring money among multiple accounts, using any account 
+;; mechanism that serializes deposit and withdrawal transactions, for 
+;; example, the version of make-account in the text above.
+
+(define (transfer from-account to-account amount)
+  ((from-account 'withdraw) amount)
+  ((to-account 'deposit) amount))
+
+#|
+
+Since withdraw and deposit themselves are 'atomic' (or rather 'safe')
+there is no problem with this routine. 
+
+|#
\ No newline at end of file