First term ,a=4 , common difference =4-7=-3, n =50
sum of first 50terms= (50/2)[2×4+(50-1)(-3)]
=25×[8+49]×-3
=25×57×-3
=25× -171
= -42925
derivation of the formula for the sum of n terms
Progression, S
S=a1+a2+a3+a4+...+an
S=a1+(a1+d)+(a1+2d)+(a1+3d)+...+[a1+(n−1)d] → Equation (1)
S=an+an−1+an−2+an−3+...+a1
S=an+(an−d)+(an−2d)+(an−3d)+...+[an−(n−1)d] → Equation (2)
Add Equations (1) and (2)
2S=(a1+an)+(a1+an)+(a1+an)+(a1+an)+...+(a1+an)
2S=n(a1+an)
S=n/2(a1+an)
Substitute an = a1 + (n - 1)d to the above equation, we have
S=n/2{a1+[a1+(n−1)d]}
S=n/2[2a1+(n−1)d]
Answer:
153.94 mm^2
Step-by-step explanation:
area of base = area of a circle = Pi * radius squared
radius squared = 49
area of base = Pi * 49
area of base = 153.94
The diagram shows a lawn with the north side measuring 50 units and the west side measuring 28 units. The deck is scaled down by a factor of 1/5.
This is because the ratio of the length of the lawn to that of the deck is 1 : 5.
Hence we can now ca
Answer:
A rotation is when a shape rotates across the x or y axis on a coordinate plane :)
Step-by-step explanation:
Just multiply 1/4 times 6