Work out $(3.42 \times 10^7) + (7.5 \times 10^4)$
Give your answer in standard form. - Edexcel - GCSE Maths - Question 8 - 2019 - Paper 2
Question 8
Work out $(3.42 \times 10^7) + (7.5 \times 10^4)$
Give your answer in standard form.
Worked Solution & Example Answer:Work out $(3.42 \times 10^7) + (7.5 \times 10^4)$
Give your answer in standard form. - Edexcel - GCSE Maths - Question 8 - 2019 - Paper 2
Step 1
Step 1: Convert to the same power of ten
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Answer
To add the two terms, we need them to have the same power of ten. Here, we have:
3.42×107
7.5×104 can be rewritten in terms of 107 as follows:
7.5×104=7.5×104×103103=7.5×107×10−3=0.0075×107
Thus we can rewrite:
3.42×107+0.0075×107
Step 2
Step 2: Calculate the sum
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Answer
Now that both terms are in the same form, we can add them:
3.42+0.0075=3.4275
So,
3.42×107+7.5×104=3.4275×107
Step 3
Step 3: Express in standard form
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Answer
In standard form, we express this as:
3.4275×107
The final answer is therefore:
4.57×107
