Soru

Zorluk: Çok zorDecimals and Scientific Notation

Let M=3.2×105M = 3.2 \times 10^{-5} and N=8.0×104N = 8.0 \times 10^{-4}. Which of the following statements must be true? Select all that apply.

  1. NM=7.68×104N - M = 7.68 \times 10^{-4}Cevap
  2. The ratio NM\frac{N}{M} is equal to 2525Cevap
  3. C
    MN=1.6×105\sqrt{M \cdot N} = 1.6 \times 10^{-5}
  4. D
    M+N=1.12×103M + N = 1.12 \times 10^{-3}
  5. 1M=3.125×104\frac{1}{M} = 3.125 \times 10^4Cevap

Cevap

The correct statements are NM=7.68×104N - M = 7.68 \times 10^{-4}, the ratio NM\frac{N}{M} is equal to 2525, and 1M=3.125×104\frac{1}{M} = 3.125 \times 10^4.
The statement NM=7.68×104N - M = 7.68 \times 10^{-4} is true because expressing both numbers with the exponent 10410^{-4} gives (8.00.32)×104=7.68×104(8.0 - 0.32) \times 10^{-4} = 7.68 \times 10^{-4}. The statement that the ratio NM\frac{N}{M} is equal to 2525 is true because 8.03.2×104(5)=2.5×10=25\frac{8.0}{3.2} \times 10^{-4 - (-5)} = 2.5 \times 10 = 25. The statement 1M=3.125×104\frac{1}{M} = 3.125 \times 10^4 is true because 13.2×105=0.3125×105=3.125×104\frac{1}{3.2} \times 10^5 = 0.3125 \times 10^5 = 3.125 \times 10^4.

Adım Adım Çözüm

1
Evaluate NMN - M
NM=7.68×104N - M = 7.68 \times 10^{-4}
Convert MM to the exponent 10410^{-4}: M=0.32×104M = 0.32 \times 10^{-4}. Then NM=(8.00.32)×104=7.68×104N - M = (8.0 - 0.32) \times 10^{-4} = 7.68 \times 10^{-4}.
2
Evaluate NM\frac{N}{M}
NM=25\frac{N}{M} = 25
Divide coefficients and subtract exponents: 8.03.2×104(5)=2.5×101=25\frac{8.0}{3.2} \times 10^{-4 - (-5)} = 2.5 \times 10^1 = 25.
3
Evaluate MN\sqrt{M \cdot N}
\sqrt{M \cdot N} = 1.6 \times 10^{-4}
Compute MN=25.6×109=2.56×108M \cdot N = 25.6 \times 10^{-9} = 2.56 \times 10^{-8}. Take the square root: 2.56×108=1.6×104\sqrt{2.56} \times \sqrt{10^{-8}} = 1.6 \times 10^{-4}.
4
Evaluate M+NM + N
M+N=8.32×104M + N = 8.32 \times 10^{-4}
Express with common powers of ten: 0.32×104+8.0×104=8.32×1040.32 \times 10^{-4} + 8.0 \times 10^{-4} = 8.32 \times 10^{-4}.
5
Evaluate 1M\frac{1}{M}
1M=3.125×104\frac{1}{M} = 3.125 \times 10^4
Compute 13.2×105=0.3125×105=3.125×104\frac{1}{3.2 \times 10^{-5}} = 0.3125 \times 10^5 = 3.125 \times 10^4.

Anahtar Kavram

Operations with numbers in scientific notation and place value adjustments
Bu soruyu puanla