# Thread: ok whats wrong/right about this answer?

1. ## ok whats wrong/right about this answer?

the question is hair grows about 29 in/day find the rate at which it grows in nm/sec

so i did this 2.54 x 10^5(<--in to nm) times 29 in = 7.366 x10 ^8
1 day = 86,400 sec

so 7.366 x 10^8 nm/ 86,400s =8.5255 x 10^3 nm/sec

^correct?

2. Originally Posted by gabriel
the question is hair grows about 29 in/day find the rate at which it grows in nm/sec

so i did this 2.54 x 10^5(<--in to nm) times 29 in = 7.366 x10 ^8
1 day = 86,400 sec

so 7.366 x 10^8 nm/ 86,400s =8.5255 x 10^3 nm/sec

^correct?
Your calculations are OK

... though I would prefer to use the units too:

$\dfrac{29\ in \cdot 2.54 \dfrac{cm}{in} \cdot 10^7 \dfrac{nm}{cm}}{1 d \cdot 24 \dfrac{h}{d} \cdot 60\dfrac{min}{h} \cdot 60 \dfrac{s}{min}}$

3. i simplified it bcuz i dont know how to use the texts in this forum sorry