Class interval should always be a whole number and yet in this case we have a decimal number. The solution to this problem is to round off to the nearest whole number. In this example, 2.8 gets rounded up to 3. So now our class width will be 3; meaning that we group the above data into groups of 3 as in the table below.
Skeletons come in a number of forms, each suited for a particular set of lifestyles and environments. Skeletons can be rigid, semirigid, or soft. They can also be external or internal. Vertebrates have internal skeletons, called bony skeletons, which consist mainly of calcified bone tissue. Most invertebrates, such as insects, spiders, and crustaceans, have outer skeletons called exoskeletons.
From Wikipedia, the free encyclopedia. The appendicular skeleton is the portion of the skeleton of vertebrates consisting of the bones or cartilage that support the appendages. Appendages appeared as fins in early fishes, and subsequently evolved into the limbs of tetrapods.rom Wikipedia, the free encyclopedia. The appendicular skeleton is the portion of the skeleton of vertebrates consisting of the bones or cartilage that support the appendages. Appendages appeared as fins in early fishes, and subsequently evolved into the limbs of tetrapods.