This number is written in extended form. Each multiplication determines the place the digit is in the number you have to determine.
4*100 → This indicates that the first digit of the number is in the place of the "hundreds", if you solve the multiplication the result is 400
2*10 → This multiplication indicates that the second digit of the number is in the place of the "tens", the result of the multiplication is 20
4*1 → This multiplication indicartes that the third digit of the number represents the "units", te result of the multiplication is 4
After the units you have to put the decimal point and all digits below it will be decimal values.
7*(1/10) → The first digit after the decimal point is in the "tenths" place, you can write it as 0.7
7*(1/100) → This indicates that this digit is in the second place after the decimal dot, in the "hundredths" place, you can write it as 0.07
0*(1/1000)→ The multiplication indicates that the digit is in the third place after the decimal dot, in the "thousands" place, you can write it as 0.000
To write the number in decimal form you have to put each digit in their given order, or add the result of each multiplicatin toghether:
400+20+4+0.7+0.07+0.000
424.770