He spent $8.14 on the apples in total. Multiple 2.20 and 2.5 to get 5.5 and then multiply 2.20 by 1.2 to get 2.64. Add up 5.5 and 2.64 to get 8.14
From 1846 to 1847 it’s -40% and from 1847 to 1848 it’s 123.3%
C= x2-x1/ x-1
The given numbers are a set of points. To convert this into a linear data set, you can do data fitting. The easiest way to do this is using a software. In this case, I used MS Excel. You plot the points and set a linear trendline. The linear equation for this set of data is: y = 0.286x + 0.784
You can refer to the image to further understand the procedure.
The answer would be 4.5 or 4 1/2
Pythagorean theorem
for a right triangle with legs legnth a and b and hytponuse c
a^2+b^2=c^2
the legnht of th eladder is the hypotnuse
the 3 feet is bottom leg
height is other leg
10=c
3=a
b=?
3^2+b^2=10^2
9+b^2=100
minus 9 both sides
b^2=91
sqrt both sides
b=√91
aprox
b=9.53939
answer is √91 feet or aprox 9.53939