0 vote
What should come in place of the question mark (?) in the following questions ?
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What should come in place of the question mark (?) in the following questions ?
$$7^{8.9} \div (343)^{1.7} \times (49)^{4.8} = 7^{?}$$
1). 13.4
2). 12.8
3). 11.4
4). 9.6
2 answers
2 vote
Solution
Expression : $7^{8.9} \div (343)^{1.7} \times (49)^{4.8} = 7^{?}$
=> $(7)^{8.9} \times \frac{1}{(7)^{3 \times 1.7}} \times (7)^{2 \times 4.8} = (7)^x$
=> $(7)^{8.9 - 5.1 + 9.6} = (7)^x$
=> $x = 8.9 + 9.6 - 5.1 = 13.4$
3 vote
Solution
Expression : $7^{8.9} \div (343)^{1.7} \times (49)^{4.8} = 7^{?}$
=> $(7)^{8.9} \times \frac{1}{(7)^{3 \times 1.7}} \times (7)^{2 \times 4.8} = (7)^x$
=> $(7)^{8.9 - 5.1 + 9.6} = (7)^x$
=> $x = 8.9 + 9.6 - 5.1 = 13.4$