If y varies inversely as x, and y = 30 when x = 0.4, find y when x = 40.
y=___
2007-05-11 20:16:36 · 6 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
x1.y1 = x2.y2 is the relationship here
y2 = x1.y1/x2 = (30 x 0.4) / 40 = 12/40 = 3/10 = 0.3
So, y = 0.3 when x = 40
2007-05-11 20:25:07 · answer #1 · answered by Swamy 7 · 0⤊ 0⤋
When a value varies inversely from another, it's really saying:
y*x = C, where C is a constant.
If y=30 when x=0.4, then 30*0.4=C, which means that C=12.
This means that when x=40, y must equal a value that makes the equation 40*y = 12. The only value that can cause this is y=0.3.
2007-05-11 20:27:11 · answer #2 · answered by Jayce 2 · 0⤊ 0⤋
since y varies inversely as x, when x is multiplied by n, y is divided by n. here n = 10, so when x is 40, y is 3.
2007-05-11 20:27:56 · answer #3 · answered by holdm 7 · 0⤊ 0⤋
y2/y1 = x1/x2
y2 = x1/x2 * y1 = 0.4/40 * 30 = 0.3
2007-05-11 20:33:31 · answer #4 · answered by Anonymous · 0⤊ 0⤋
dang i just dont get math. lol sorryy
2007-05-11 20:23:45 · answer #5 · answered by ♥Brunette♥ 3 · 0⤊ 0⤋
invertebrates
2007-05-11 20:28:24 · answer #6 · answered by Thomas 2 · 0⤊ 0⤋