神算子挑战赛-减法，极速提升减法运算能力 at Mac App Store analyse

A calculating game parents and kids can play together to achieve incredible improvement! -----Calculating Genius Competition - Subtraction Train the comprehensive subtraction skills! Greatly improve leaners correctness and speed of subtraction within an idealy short period! Challenge calculating geniuses around the world! Cultivate concentration habits in learning. -----Incredible! After 2-3 weeks of playing the game, even pre-school kids can do much better in calculation than primary students without special training! -----Contents The game, designed carefully and based on the learning habits of young kids, consists of 19 progressive levels, which scientifically involve factors such as numbers, terms, borrows, subtraction skills. -----Knack! 80 marks secure the clearing of each level. It is, however, strongly suggested: Do each level several times to get the highest marks possible (＞1000), make sure to be the winner in the competition! -----level Information Level:4 Minuend ：＜15 Terms：2 Borrows： 0/1 Secs/Per ：5 Level:5 Minuend ：＜20 Terms：2 Borrows： 0/1 Secs/Per ：5 Level:6 Minuend ：＜20 Terms：3 Borrows： 0 Secs/Per ：8 Level:7 Minuend ：＜20 Terms：3 Borrows： 1 Secs/Per ：8 Level:8 Minuend ：＜50 Terms：2 Borrows： 0 Secs/Per ：8 Level:9 Minuend ：＜50 Terms：2 Borrows： 1 Secs/Per ：8 Level:10 Minuend ：＜100 Terms：2 Borrows： 0 Secs/Per ：8 Level:11 Minuend ：＜100 Terms：2 Borrows： 1 Secs/Per ：8 Level:12 Minuend ：＜100 Terms：3 Borrows： 0 Secs/Per ：12 Level:13 Minuend ：＜100 Terms：3 Borrows： 1 Secs/Per ：12 Level:14 Minuend ：＜1000 Terms：2 Borrows： 0 Secs/Per ：12 Level:15 Minuend ：＜1000 Terms：2 Borrows： 1 Secs/Per ：12 Level:16 Minuend ：＜1000 Terms：2 Borrows： 2 Secs/Per ：15 Level:17 Minuend ：＜1000 Terms：3 Borrows： 0 Secs/Per ：15 Level:18 Minuend ：＜1000 Terms：3 Borrows： 1 Secs/Per ：15 Level:19 Minuend ：＜1000 Terms：3 Borrows： 2 Secs/Per ：15