18 of 18 people found the following review helpful
Definately worth a read!,
By A Customer
This review is from: The Trachtenberg Speed System of Basic Mathematics (Paperback)
A good book for those who want better mental arithmetic skills. Whilst a large number of the basic techniques applied were discovered by mathematicians well before Trachtenburg was born (Euler and Cauchy come to mind), this is almost certainly the first time that the thinking was brought to bear on simple arithmetic in such a systematic fashion.