The mean can be found by adding the two numbers and dividing by 2
let the second number be y
(x + y)/2 = 1/2x + 1
solve for y
multiply each side by 2
x + y = 2(1/2x + 1)
distribute
x + y = x + 2
subtract x on both sides
y = 2
ANSWER: the second number is 2
Answer: 122
Explanation: 250 - 5 = 245
(The 5 comes from the president, Vice President, two volunteers, and guess speaker)
245/2 = 122.5
Half a couple cannot attend so the answer would be 122 couples can attend