测测孩子的数学潜力？

chrisyue

1. 2003被5除余数是3,所以答案应该是C.
2.suppose father's age is x, then the son's age is x-(36-8)=x-28
then x=3*(x-28)   x=42
the father is 42 years old.
4. if 90 is the highest mark, a person's mark is 45. the average mark is 64. the total mark is 64*8=512 the last person's mark is 512-(74+48+90+33+60+78+45)=158>100
so 90 is not the highest score.
suppose the highest mark is x. the last person's mark is x/2.
so 74+48+90+33+60+78+x+x/2=64*8
x=86<90
86 is not the right answer.
because 74*2 and 60*2 and 78*2 are more than 100, and 33*2<90. and 48*2=96>90
so wu's score is 96. another person's mark is 64*8-(74+48+90+33+60+78+96)=33