Which of these is correct?(1 point)

Question

Responses

(8.8×108)(4.2×107)=13×1015
open paren 8 point 8 times 10 to the 8th power close paren times open paren 4 point 2 times 10 to the 7th power close paren is equal to 13 times 10 to the 15th power

(9.9×107)(5.8×106)=5.72×1013
open paren 9 point 9 times 10 to the 7th power close paren times open paren 5 point 8 times 10 to the 6th power close paren is equal to 5 point 7 2 times 10 to the 13th power

(4.6×105)(2.1×104)=2.5×10
(4.6×105)(2.1×104)=2.5×10

(2.9×108)(1.3×107)=3.77×1015

Answer 1

To check which of these calculations is correct, we can perform the multiplication step by step for each expression in scientific notation.

1. (8.8×10^8)(4.2×10^7):

   • Multiply the coefficients: 8.8 × 4.2 = 37.06
   • Add the exponents: 8 + 7 = 15
   • Therefore: (8.8 × 10^8)(4.2 × 10^7) = 37.06 × 10^15
   • This can be expressed in proper scientific notation as 3.706 × 10^16, not 13 × 10^15.

2. (9.9×10^7)(5.8×10^6):

   • Multiply the coefficients: 9.9 × 5.8 = 57.42
   • Add the exponents: 7 + 6 = 13
   • Therefore: (9.9 × 10^7)(5.8 × 10^6) = 57.42 × 10^13
   • This can be expressed in proper scientific notation as 5.742 × 10^14, not 5.72 × 10^13.

3. (4.6×10^5)(2.1×10^4):

   • Multiply the coefficients: 4.6 × 2.1 = 9.66
   • Add the exponents: 5 + 4 = 9
   • Therefore: (4.6 × 10^5)(2.1 × 10^4) = 9.66 × 10^9, not 2.5 × 10.

4. (2.9×10^8)(1.3×10^7):

   • Multiply the coefficients: 2.9 × 1.3 = 3.77
   • Add the exponents: 8 + 7 = 15
   • Therefore: (2.9 × 10^8)(1.3 × 10^7) = 3.77 × 10^15, which is stated correctly.

Based on these calculations, the only correct statement is:

(2.9×10^8)(1.3×10^7)=3.77×10^15