How many significant figs are in these problems

0.00007662*825.613= 0.06325846806

7662000.0*0.00825613=63258.46806

explain plz

Both of these are multiplication problems. The rule for significant figures for a multiplication/division problem is that the final answer can have no more significant figures than the multiplier that has the least amount.

0.00007662 has 4 sig. figs. The zeroes in front of the decimal number are place holders only and are not SF.

825.613 has 6 sig. figs (all nonzero digits are significant)

The product (0.06325846806) should only be reported to 4 SF since the first multiplier had only 4 SF.
Answer: 0.06326 (rounded up from 0.063258).

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7662000.0 . . .Since this number has a decimal point in it, you assume that all 8 digits are SF.
If the number were written as 7662000 with no decimal point, you would assume only 4 SF (7662).

0.00825613 . . .Again, the initial zeroes do not count and there are 6 SF.

The final answer should have 6 SF since the second factor has the lesser number of SF (6).
Answer: 63258.5 (rounded up from 63258.46).

for multiplication: round to the least number of digits in any factor.

0.00007662 (4 digits) *825.613 (6 digits)= 0.06325846806 (round to 4 digits = 0.06326)
leading zeroes in a decimal number are not sig.

7662000.0 (8 digits) * 0.00825613 (6 digits) = 63258.46806 (round to 6 digits = 63258.5)
trailing zeroes in a decimal number are sig.
so the 0 after the decimal place makes all the preceding zeroes sig.

11 for the first
10 for the second

sig figs are counted after the decimal or whole numbers including decimals. u dont count 0s if there are no decimals after it