As the sum of marks of others remain unchanged , let their sum be x . As the mean using 83 was 40 , we have ,
(x +83)/100 = 40
x + 83 = 4000
x = 3917
Now mean using 53 ,
(x +53)/100
(3917+53)/100
39.7.
Hope it helps , plz mark as brainiest :-)
Answer:
Step-by-step explanation:
42 × 48
(40 + 2) × (40 + 8)
40 × (40 + 2) = (40 × 40) + (40 × 2) = 1600 + 80 = 1680
8 × (40 + 2) = (40 × 8) + (2 × 8) = 320 + 16 = 336
Then 1680 + 336 = 2016
You need to swap the x values around. They need to be given in the same order as the y values. The sum should be:
Answer:
x₍ₙ₎ = x₍₁₎ * (-5)ⁿ⁻¹
Step-by-step explanation:
x₍ₙ₎ = x₍₁₎ * (-5)ⁿ⁻¹
x₍₁₎ = -2
x₍₂₎ = (-2) x (-5)²⁻¹ = (-2) x (-5) = 10
x₍₃₎ = (-2) x (-5)³⁻¹ = (-2) x (-5)² = -50
