Answer:
The rate of interest is 20% and the sum is $3,750
Step-by-step explanation:
In order to calculate the sum and rate of interest we would have to make the following calculation:
rate of interest= (sum in 4 years-sum in 3 years)*100/sum in 3 years*1
According to the given data we have the following:
sum in 4 years=$7,776
sum in 3 years=$6,480
Therefore, sum in 4 years-sum in 3 years=$7,776-$6,480=$1,296
Therefore, rate of interest=$1,296*100/$6,480*1
rate of interest=20%
To calculate the sum we would have to make the following calculation:
FV=PV(1+20%)∧3
$6,480=PV(1,20)∧3
PV=$3,750
Sum is $3,750
Answer:

Step-by-step explanation:
Given:
For every 1/2 of an hour that the turtle is crawling, he can travel 3/20 of a mile
Question asked:
At what unit rate is the turtle crawling?
Solution:
As here<u> time taken is given</u> and the <u>distance traveled is also given </u>and hence we will apply speed and distance formula to find rate of crawling of turtle.
Time taken by turtle = 
Distance which can be traveled by turtle = 


Therefore, the rate at which the turtle is crawling is 
The Correct answer is
(n)(4) = (7)(8)
4n = 56
n = 14
There would be 107 whistles
-equation- 235-128=107