108 PSYCHOLOGICAL METHODS OF TESTING INTELLIGENCE 



supplement age 7, and therefore have the value 9/7 each, the re- 

 maining 3 tests in the 7th year and likewise the 5 tests in the 8th 

 year count for their own level, and thus figure 1 each. 



3 x 1 3 tests 



9 

 2 X = 2.6 tests 



5 X ! =5 tests 

 10.6 tests 



These 10.6 tests indicate a supplement of 2.1 years ; so Child B 

 gets a mental age of 8.1 years and his inferiority to Child A is 

 now brought out statistically. 



