Number 1. <span>So the duck's OWN speed (if flying without any wind) with the wind behind him is: Where x/10 is the wind speed The duck's OWN speed (if flying without any wind) with the wind against him is: Where x/10 is the wind speed Remember So we have two equations that must equal each other since they both represent the duck's speed. We need to rearrange to find x
Add x/10 to both sides and subtract (1600/10 from both sides gives:
so x must be 400/10 which 40 metres per minute.
Number 2. </span>let s=salmon and c=current <span> upstream __ s-c=100m/20 min __ s-c=5m/min
downstream __ s+c=100m/8min __ s+c=12.5m/min
adding the two equations __ s-c+(s+c)=5+12.5 __ 2s=17.5 __ s=8.75m/min
<span>If the clock is held at a
constant 0.0ºc over a period of 24 hours, the clock will be exactly the same as
the perfect clock because it is at a
constant 0.0</span> <span>ºc for 24. Meaning there is
no deviation on its reading</span>
