A.1185. How many 3-digit numbers contain the digit 5 exactly once?
A.1186. Five girls and three boys want to play soccer. How many different ways can they make two teams of 4 players if each team must have at least one boy?
A.1187. Make as many 3-digit numbers as you can using the digits 5, 6, and 7 exactly once in each number. What is the sum of all those numbers?
A.1188. We painted a 10 cm x 10 cm x 10 cm cube red. Then we cut it up into 1 cm x 1cm x 1cm little cubes by cuts parallel to the sides of the big cube. How many of the little cubes have red paint on them?
A.1189. Is it true that you can always find two numbers among six odd numbers whose difference is divisible by 10?
A.1190. Is it true that you can always find two numbers among 4 odd numbers whose difference or sum is divisible by 10?
A.1191. How many square numbers are there from 1 to 2018?
A.1192. In some of the 3-digit numbers every digit is less than 4. How many such numbers are there?
Please send your solutions here.
The Sharma Kamala Educational Trust is sponsoring the participation of students from India. So, if you are a student living in India, please, send your solutions to: Group A from India
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