77.6 is about twice the value of 38. So d8 must go into 776 2 times, 20 times, 200 times, etc. Changing that 77.6 number back to 776 must add one decimal place to 2 times, and it becomes 20 times.
The actual times is about 20.42, so the estimate was pretty close.
53
Round 38 to 40. Estimate the product as 80. The actual product is 76.
A factor = a number which can be divided into the given number with no remainder| Known factors of 38: 1, 2, 19, 38| Prime numbers: numbers that can only be multiplied one time/ numbers with only one set of numbers/ numbers that can only be divided one time.
40 x 30 = 1200
94.1053
20.4211
20.4211
0.049
38
53
51 divided 38 = 1.3421052631578947
1.9
53
17
2
38
0.6786