X/15 = 10/20
20x = 150
x = 150/20
x = 7.5
X=6
First subtract 11 from both sides and you'll get 5x^2=180 then divide 180 by 5 which equals 36 you get x^2=36 find square root of 36 is 6
This is the concept of arithmetic. To calculate the percentage of time life has existed we proceed as follows;
According to history:
The age of earth is 4.6 billion years
the age of life is as it appeared from unicellular is 3.8 billion years.
thus the percentage of the above will be:
3.8/4.6 x 100
=0.82609x100
=82.609%
Answer:
Your answer is 61.
Step-by-step explanation:
Simple enough! We simply round up each cost to the nearest whole dollar. $6.50 can be rounded to $7, $15.75 can be rounded up to $16, $2.25 can be rounded up to $3 (Note we're rounding up, in normal rounding we would round down to $2). Finally, $7.25 can be rounded up to $8.
Next comes simple algebra,

Therfore, your overestimate of the cost would be 61.