Let x = the larger number      y = the smaller number x + y = 51 x - y = 13 ==> x = y + 13 substitute y + 13 back into the first equation and solve for y (y + 13) + y = 51   2y + 13 = 51 2y + … Read more

9999 - 999 = 9000

2 x 30 + 2 x W > 100      60 + 2 x W > 100   2 x W > 100 - 60   2 x W > 40   W > 40/2   W > 20 Check: 2 x 30 + 2 x 21 > 100   60 + 42 > 100   … Read more

Just divide 7 by 11 7/11 7.0/11 = 0.6363...

Let x = a number 5x - 5 = 3x + 7 5x - 3x - 5 = 3x - 3x + 7 2x - 5 = 7 2x - 5 + 5 = 7 + 5 2x = 12 2x/2 = 12/2 x = 6 check: 5(6) - 5 = 3(6) + 7 30 … Read more

The GCF is the largest number that can divide a number First get the prime factors of each number 42 = 2 * 3 * 7 63 = 3 * 3 * 7 the GCF = 3 * 7 = 21

The mean is the average: Add all numbers together then divide by the count of the numbers you just added the mode is the number that appears the most in your group of numbers the median is the number that is in the middle of your group of numbers 3, 7, 10, 12, 14, 10, … Read more

5/12 this is the same as saying "5 divided by 12" this is difficult to display here so here you go: 12 goes into 5.0 four times with 2 left over returning: 4 2/12 => 4 1/6 => 4.1666....

Since the only even that is prime is 2, we know all three numbers are odd and we know that the smallest and next to smallest ones must be less than 20, the 2nd because we know that 20 is not prime because it's even 17,19,23 17+19+23 59

3/5 ?>? 4/6 this can be done in many ways: 1. Number line(can't really display it here) 2. Use least common multiple on of the denominators so we can force them to be the same you can start with the product of them: 5 * 6 = 30 so we multiply the left side of … Read more

Give send

The square root of 2x + 1 can be written as (2x + 1)^1/2 x = 7 + (2x + 1)^1/2 square both sides (x - 7)² = ((2x + 1)^1/2) ² x² -14x + 49 = 2x + 1 x² -14x + 49 - 2x - 1 = 0 x² - 16x + 48 … Read more

Let x = prime number x < 19 since the sum of the digits is > 7, then x >= 11 since it is prime possible primes are 11,13,17 sorry I could not come up with an equation to prove this, but the answer has to be 17 since it is the only prime whose … Read more

Thousands place = 1000 (2 x Ones place) Ones place = 1 x (2 x Hundreds place) Hundreds place = 100 x (2 x Tens place) Putting all in terms of ones: Let x = ones place x/4 = tens place x/2 = hundreds place 2x = thousands place 1000 * (2x) + 100 * … Read more