Hope and Winkie Peabody are both 90 yrs old. Katherine Hill, on the other hand, is one and a half times as old as she was when she was one and a half times as old as she was when she lacked 5 years of being half as she is now. How old is Katherine?
2007-01-01 12:08:06 · 4 answers · asked by kasaysayan 1 in Science & Mathematics ➔ Mathematics
Katherine now = K
When she lacked 5 years of being half of now = .5K-5
So, 1.5 times as old as when she lacked 5 years, etc. = 1.5 (.5K-5), or .75K - 7.5
So, Katherine is 1.5 times as old as that, or
K = 1.5 (.75K - 7.5)
K = 1.125K - 11.25
11.25 = .125K
90 = K
Katherine's 90 years old, too.
2007-01-01 12:20:05 · answer #1 · answered by HappyHeather 2 · 0⤊ 0⤋
Let
k = Katherine's age
k = (3/2)(3/2)(k/2 - 5)
k = (9/4)(k/2 - 5)
k = 9k/8 - 45/4
8k = 9k - 90
90 = k
Katherine is 90 years old also.
2007-01-01 14:12:17 · answer #2 · answered by Northstar 7 · 0⤊ 0⤋
x is current age
x*2/3*2/3 = x/2 - 5
(4/9)x = x/2 - 5
4x = 9x/2 - 45
4x + 45 = 9x/2
8x + 90 = 9x
x = 90
Katherine is 90
2007-01-01 12:23:05 · answer #3 · answered by Tom :: Athier than Thou 6 · 0⤊ 0⤋
Katherine Hill is 90 years old as well. Here is the formula to use...
Current age=1.5[1.5(0.5 x current age - 5)]
CA = 1.5[0.75CA - 7.5]
CA = 1.125CA - 11.25
11.25 = 0.125CA
CA (Current Age) = 90
2007-01-01 12:44:30 · answer #4 · answered by JT 1 · 0⤊ 0⤋