two numbers are in the ratio of 5:7 if 3 is subtracted from each of them ratio becomes 2:3 find the number
Answers
Answer:
The Phinizy Center for Water Science’s research projects often includes studying the diversity and abundance of certain macroinvertebrates. In the Oxbow Lakes left behind by the Savannah River, one type of midge larva is particularly common in the sediment samples that are collected. In fact, this midge makes up a large percentage of organisms found and counted in the sediments of the Oxbow Lakes.
The Glassworm, also known as the Phantom Midge due to its transparency, is a small insect from the family Chaoboridae. Closely related to the ever-ubiquitous Chironomidae, it is small and worm-like in its larval stage, inhabiting rivers and other natural water sources, such as the Oxbow Lakes along the Savannah River. However, the glassworm has a fascinating life history – one unlike most other insects.
Phantom Midge by Peter Maguire
Phantom Midges by Peter Maguire
One of the main things that sets the glassworm apart is its diel vertical migration. This transparent creature spends the daytime in the depths of the hypolimnion – the bottom layer of the lake – poking its head out of the dense sediment, feeding on zooplankton swimming by. However, after twilight the glassworm migrates from the sediment to the epilimnion – the uppermost layer of the lake. Two pairs of air sacs control the larva’s bouyancy and are used to move up or down the stratification zones. The exchange of gases from these airsacs are actually audible, taking up much of the perceptible frequencies underwater at dusk. One of the reasons Chaoboridae exhibits this behavior is because its prey does as well. Zooplankton migrate to the epilimnion at night due to changes in temperature and light.
Answer:
the numbers are 15 and 21
Step-by-step explanation:
Let the numbers be 5x and 7x
according to the question,
5x-3=2
7x-3=3
5x-3/7x-3=2/3
By cross mutliplication,
15x-9=14x-6
x=3
The numbers are 5x=15 and 7x= 21