The total number of marbles in the bag is 7, since 3+4=7. There are 3:4 black marbles, so 3/7 of the bag is black marbles, which can be written as 3:7.
4/7 of the bag is red marbles, which can be written as 4:7
a) If this trend continues, how many birds will be left by 2010 will be 525
b) The birds would there have been in 1990 will be 2475
<h3>What is rate of increase?</h3>
Rate of increase or decrease is defined as the increment or decrement in any quantity over a period of time constantly.
Here we have the data that:
There were 1500 birds in 2000 and they are decreasing at an annual rate of 6.5%.
a) If this trend continues, how many birds will be left by 2010
{1500x6.25}/{100}=97.5
So the bird decrement in the one year will be =97.5 so it will be in the 10 years or upto 2010 will be
97.5x10=975
So the birds left till 2010 will be:
Q=1500-975=525
b)The birds would there have been in 1990 will be:-
=1500+975=2475
Hence If this trend continues, how many birds will be left by 2010 will be 525.The birds would there have been in 1990 will be 2475
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The formula being used is V=
r^2(h/3)
V≈235
V=235.62 to be approximate
