Let x and y be the 2 parts of 15 ==> x + y=15 (given)
Reciprocal of x and y ==> 1/x +1/y ==> 1/x + 1/y = 3/10 (given)
Let's solve 1/x + 1/y = 3/10 . Common denominator = 10.x.y (reduce to same denominator)
==> (10y+10x)/10xy = 3xy/10xy ==> 10x+10y =3xy
But x+y = 15 , then 10x+10y =150 ==> 150=3xy and xy = 50
Now we have the sum S of the 2 parts that is S = 15 and
their Product = xy =50
Let's use the quadratic equation for S and P==> X² -SX +P =0
Or X² - 15X + 50=0, Solve for X & you will find:
The 1st part of 15 is 10 & the 2nd part is 5
The probability of a 2 or a 5 is 50%
Numbers are 416, 417 and 418
<u>Step-by-step explanation:</u>
Step 1:
Let the numbers be x, x + 1 and x + 2. Given that their sum is 1251.
⇒ x + x + 1 + x + 2 = 1251
⇒ 3x + 3 = 1251
⇒ 3x = 1248
⇒ x = 416
Step 2:
Find the other numbers.
⇒ x + 1 = 417 and x + 2 = 418
I think the answer is D) 8 over 32 multiplied by 7 over 31
Hopefully that helped! :)
