Hey there!!
Original value - 114.6 million tons in 1950
Decrease by 6.6% every year.
6.6% = 0.066
1951 : 114.6 - ( 0.066 × 114.6 )
... 107.03 million tons
1952 : 107.03 - ( 0.066 × 107.03 )
... 99.9 million tons
1953 : 99.9 - ( 0.066 × 99.9 )
... 93.3 million tons
1954 : 93.3 - ( 0.066 × 93.3 )
... 87.1 million tons
1955 : 87.1 - ( 0.066 × 87.1 )
... 81.3 million tons
Doing this is going to take time.
Let me given an alternate method :
Let :
x = 0
a = 114.6
Be 1950
b = 1 - ( 6.6 / 100 ) = 0.934
x = 2010 - 1950 = 60
y = the million tons remaining :
y = 114.6 ( 0.934 ˣ )
y = 114.6 ( 0.934 ⁶⁰ )
y = 1.9 million tons.
Hence, the required answer is 1.9 million tons.
Hope my answer helps!