# probability

1.) A random digit from 1 to 9 (inclusive) is chosen, with all digits being equally likely. The probability that when it's squared it will end with the digit 1.

2.) A random number between 1 and 20 (inclusive) is chosen. The probability that its square root will not be an integer.

1. 👍 0
2. 👎 0
3. 👁 394
1. 1. Find how many (initial) digits when squared gives one. Dividing that by 9 will give you the required probability.

Also, it may be of interest to note that single digits that add up to 10 have the same last digits when squared.
Example: 2²=4 8²=(10-2)²=64 also ends with the digit 4.

2. Again, determine how many "perfect squares" there are among the numbers 1 to 20. Divide that number by 20 will give you the probability.

1. 👍 0
2. 👎 0

## Similar Questions

1. ### Math

a number between 1000 and 9999, inclusive, is chosen at random. what is the probability that it contains a)no 9's? b) at least one 9?

asked by Taryn on October 3, 2013
2. ### Math

The mystery number's tens digit is less than the ones digit. The tens digit is less than the tenths digit. The tens digit is even. Its ones digit divided by its tens digit is 5. The product of two of the digits is 6 It has two odd

asked by Gene on September 25, 2012
3. ### Math

A two-digit locker combination is made up of two non-zero digits. Digits in a combination are not repeated and range from 3 through 8. Event A = choosing an odd number for the first digit Event B = choosing an odd number for the

asked by Sophia on October 8, 2019
4. ### math

A two-digit number is chosen at random.What is the probability that the chosen number is a multiple of 7 ? please answer and explain

asked by peter on December 19, 2013
5. ### math

A two-digit locker combination is made up of non-zero digits and no digit is repeated in any combination. Event A = the first digit is 4 Event B = the second digit is odd If a combination is chosen at random with each possible

asked by alyssa on April 19, 2020
1. ### math

please help! 1.) A random digit from 1 to 9 (inclusive) is chosen, with all digits being equally likely. The probability that when it's squared it will end with the digit 1. 2.) A random number between 1 and 20 (inclusive) is

asked by karen on August 11, 2012
2. ### math

using digits 1-9 only once, multiply a 3 digit by a 2 digit number and get a 4 digit result 12*345=4140? looks ok to me. the answer would have to be 6789 or some order of those digits if you used the others in the question. digits

asked by Trey on November 28, 2006
3. ### Math

Solve the mathematical puzzle. Determine the digits of R from these clues. The first digit is the answer when the third digit is divided by 2. The second and third digits add to 7. The second digit minus the first digit is 1. R is

asked by Shawna Lynn on April 29, 2013
4. ### math

Solve the mathematical puzzle. Determine the digits of Q from these clues. The first and third digits of Q are even. The second and fourth digits of Q are odd. The first digit is two times the fourth digit. The first and second

asked by beyonce on April 8, 2020
5. ### Math

I form a 3-digit number at random from the digits 1-9. What is the probability that my number has no repeated digits? All three digits the same? Exactly one repeated digit?

asked by Kay on November 12, 2012
6. ### math

Form the greatest possible 5-digit number using the clues.All five digits are different. None of the five digit are 1.The digit in the ten thousands place is greater than 7.The sum of all five digit is 18.The greatest digit is

asked by hawa on September 22, 2017