None of the items in the list.
Yes, the mean can be a decimal because the mean is a+b+c+d+(the numbers)....=e(the sum of the numbers), then e/(the quantity of numbers added together to get e)=f(the mean). Sometimes the sum may not go into the quantity in a whole number, which gives you a decimal.
5.8
It is: 300+109/100 = 301.09 as a decimal
You do not need to align decimal points when multipylng. You multiply the two numbers ignoring the decimal point but ensuring that any trailins 0s are present. The number of digits after the decimal point in the answer is the sum of the number of digits after the decimal points in the two multiplicands.
No, the sum of a repeating decimal and a terminating decimal is never a terminating decimal.
how to express the sum 257 and 431 in decimal form
You align their decimal points. Sum the numbers as normal and, in the answer, place the decimal point so that it lines up with those of the summands.
Pi to 144 decimal places is written thus: 3.14159265358979323846264338327950288419716939937510 58209749445923078164062862089986280348253421170679 82148086513282306647093844609550582231725359 The sum of these first 144 decimal digits (after the decimal point) is 666.
The ISBN of Keeping Faith is 0-688-16825-6.
Infinity.
It is 251 and there is no requirement for a decimal point.
Expressed in octal, the decimal sum 27 + 31 = 58 would be expressed: 33 + 37 = 72
It depends on your level of numerical skill. You can convert the decimal to an approximate fraction and estimate the sum of the two fractions, or you can convert the fraction to an approximate decimal and estimate the sum of the two decimals or, if you are more able you just estimate their sum directly.
The range of a single number - with or without a decimal - is zero.
The answer depends on how many decimal places are in the summands.
That depends what the divisor of the division sum is - as to what the part of the number after the decimal point would be.