Answer:
19.2
Step-by-step explanation:
The initial amount of the money is £11,000 and the interest is 3.9% per year for first 3 years and then 4.5% after that. If Dan invests it for 7 years, that means the interest would be 3 years of 3.9% and 4 years of 4.5%.
The calculation would be:
total money= initial amount * interestrate1 * interest 2
total money= £11000 *(100%+3.9%)^3<span>*(100%+4.5%)^4
</span>total money= £11000 *(103.9%)^3 * (104.5%)^4
total money= £11000 * <span>1.121622319 </span>* 1.1925186
total money= £14,713.11
Answer:
...
against the wind, an airplane travels 3640 km in 7 hours.
with the wind, the same plane travels 6000 km in 6hrs.
...
let speed of plane in still air be x mph
speed of wind be y mph.
..
t=d/r
..
against wind speed = x-y mph
with wond speed = x=y mph
...
3640/(x-y)=7
3640 = 7x-7y
/7
520=x-y.....................1
...
6000/x+y = 6
6000 = 6x+6y
/6
1000=x+y.....................2
...
Add (1) & (2)
2x=1520
/2
x=760 mph speed of plane in still air
...
plug value of x in 2
1000=760+y
100-760=y
240 = y
240 mph speed of wind
