Answer :
Answer:
1.462 × 10^20
Step-by-step explanation:
Multiplication proceeds in the usual way. The rules of exponents apply. A final exponent adjustment is needed to put the number in scientific notation form. (Your calculator can do all of this for you.)
(4.3×10^12)(3.4×10^7) = (4.3×3.4)×(10^12×10^7) = 14.62×10^(12+7)
= 14.62×10^19
= (1.462×10)×10^19 = 1.462×10^(1+19)
= 1.462×10^20
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The rule of exponents used is ...
(a^b)(a^c) = a^(b+c)
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I find it works well to estimate whether the product of the mantissas will be more than 10, then make adjustments to exponents before the multiplication:
(4.3×10^12)(3.4×10^7) = (4.3×10^12)(0.34×10^8) = 1.462×10^(12+8)
= 1.462×10^20