Between 2000 and 2014 , the number of twin births in a certain country increased by 15 %, to approximately 133975. About how many twin births were there in 2000?

116500

Step-by-step explanation:

We are looking for the number of twin births in 2000.

Let the number of twin births in 2000 be x.

The number of twin births in 2000 is 100% of the number of births in 2000 since 100% of something is the entire thing.

The number of twin births went up 15% from 2000 to 2014, so in 2014, the number of twin births was 100% of the number of twin births plus another 15% of the number of twin births.

100% + 15% = 115%

The number of twin births in 2014 was 115% of x.

The number of twin births in 2014 was 133975.

115% of x = 133975

115% * x = 133975

1.15x = 133975

x = 133975/1.15

x = 116500

The number of twin births in 2000 was 116500.

116,500.

Step-by-step explanation:

The equation is

x + 0.15x = 133975 where x = the number of twin births in the year 2000.

1.15x = 133975

x = 133975 / 1.15

= 116,500.