Let's call your number n. Twice your number is 2n. The product of your number and twice your number (so n multiplied by 2n) is 128.
Set up an equation:
n × 2n = 128
2n² = 128
Divide both sides by 2:
n² = 64
Square root both sides to isolate n:
n = 8
The question asks for half your number, so just half 8:
8 ÷ 2 = 4.
Half your number is 4.
<u>Answer:</u>
Ptolemy accounted for 'retrograde motion' in his model of the solar system by introducing smaller circles named 'epicycles'.
<u>Explanation:</u>
- According to Ptolemy, the Sun and the other planets in the Solar system orbited around the Earth.
- The Greeks were convinced that Ptolemy's earlier model did not provide for backward or the retrograde motion.
- Ptolemy thought over it for a while and theorized the possibility of 'epicycles'.
- According to Ptolemy, the planets that orbited Earth also orbited another smaller point.
- The smaller orbits followed by the planets while in motion around the Earth in a larger orbit were introduced by Ptolemy as 'epicycles'.
- Until Kepler proposed his models of the functioning of the Solar system, Ptolemy's models were considered the most relevant.
the world's current population is 7.3 billion and the world population in 1915 was 1.8 billion. The increase over the past century is 7.3 billion - 1.8 billion = 5.5 billion. So, the correct answer would be "more than 5 billion" (option D).
Answer:
Number one is D and umber number two is C
Explanation:
There ya go