Question

find the value of the following:
f) -19/14÷(-19/-28)
please answer class-7 ​

Answer 1

Answer

$q[q+1]/2$

He seems to be unaware that n itself has to be prime. He also says (wrongly) that the perfect numbers end in 6 or 8 alternately. (The first 5 perfect numbers end with digits 6, 8, 6, 8, 6; but the sixth also ends in 6.) Philo of Alexandria in his first-century book "On the creation" mentions perfect numbers, claiming that the world was created in 6 days and the moon orbits in 28 days because 6 and 28 are perfect. Philo is followed by Origen,[5] and by Didymus the Blind, who adds the observation that there are only four perfect numbers that are less than 10,000. (Commentary on Genesis 1. 14-19).[6] St Augustine defines perfect numbers in City of God (Book XI, Chapter 30) in the early 5th century AD, repeating the claim that God created the world in 6 days because 6 is the smallest perfect number. The Egyptian mathematician Ismail ibn Fallūs (1194–1252) mentioned the next three perfect numbers (33,550,336; 8,589,869,056; and 137,438,691,328) and listed a few more which are now known to be incorrect.[7] The first known European mention of the fifth perfect number is a manuscript written between 1456 and 1461 by an unknown mathematician.[8] In 1588, the Italian mathematician Pietro Cataldi identified the sixth (8,589,869,056) and the seventh (137,438,691,328) perfect numbers, and also proved that every perfect number obtained from Euclid's rule ends with a 6 or an 8

Answer 2

$\frac{ - 19}{14} \div \frac{ - 19}{ - 28} \\ = \frac{ - 19}{14} \times \frac{ -28}{ - 19} \\ = \frac{ - 19}{14} \times \frac{28}{ 19} \\ = \frac{ - 19 \times 28}{14 \times 19} \\ = \frac{ - 1 \times 28}{14 \times 1} \\ = \frac{ - 1 \times 2}{1} \\ = -2 \\ it \: is \: the \: answer \: \\ hope \: it \: helps$