Maths Quiz 19.04.2009

1. **The sum of the even numbers between 1 and n is 79*80, where n is an odd number, then n=?**

First term a=2, common difference d=2 since even number

therefore sum to first n numbers of Arithmetic progression would be

n/2(2a+(n-1)d)

= n/2(2*2+(n-1)*2)=n(n+1) and this is equal to 79*80

therefore n=79 which is odd...

Explanation

First term a=2, common difference d=2 since even number

therefore sum to first n numbers of Arithmetic progression would be

n/2(2a+(n-1)d)

= n/2(2*2+(n-1)*2)=n(n+1) and this is equal to 79*80

therefore n=79 which is odd...

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4. The price of a bushel of corn is currently $3.20, and the price of a peck of wheat is $5.80. The price of corn is increasing at a constant rate of 5x cents per day while the price of wheat is decreasing at a constant rate of cents per day. What is the approximate price when a bushel of corn costs the same amount as a peck of wheat?

$4.50

$5.10

$5.30

$5.50

$5.60

5. AB + CD = AAA, where AB and CD are two-digit numbers and AAA is a three digit number; A, B, C, and D are distinct positive integers. In the addition problem above, what is the value of C?

1

3

7

9

Can not be determined

Maths Quiz 19.04.2009

1. **The sum of the even numbers between 1 and n is 79*80, where n is an odd number, then n=?**

2.

What first name or nickname would you like us to use?

2. How many randomly assembled people do u need to have a better than 50% prob. that at least 1 of them was born in a leap year?

3. In a basketball contest, players must make 10 free throws. Assuming a player has 90% chance of making each of his shots, how likely is it that he will make all of his first 10 shots?

5. AB + CD = AAA, where AB and CD are two-digit numbers and AAA is a three digit number; A, B, C, and D are distinct positive integers. In the addition problem above, what is the value of C?

Maths Quiz 19.04.2009

1. The sum of the even numbers between 1 and n is 79*80, where n is an odd number, then n=?

2.

What first name or nickname would you like us to use?

2. How many randomly assembled people do u need to have a better than 50% prob. that at least 1 of them was born in a leap year?

3. In a basketball contest, players must make 10 free throws. Assuming a player has 90% chance of making each of his shots, how likely is it that he will make all of his first 10 shots?

5. AB + CD = AAA, where AB and CD are two-digit numbers and AAA is a three digit number; A, B, C, and D are distinct positive integers. In the addition problem above, what is the value of C?

1. **The sum of the even numbers between 1 and n is 79*80, where n is an odd number, then n=?**