You divide 18 by 90 and get .2 then multiply it by 100 and get 20. Then you subtract 20 from 100 and get 80. You got 80% correct.
A rational number is one which can be represented using fractions. The opposite of division is multiplication and vice versa. Knowing this information, you can easily go about turning a division of two fractions into the multiplication of two fractions.
Ex.
(1/2) / (3/4) = ?
multiply the denominator of your fraction by the reciprocal of the denominator.
(1/2)*(4/3) / (3/4)*(4/3)
(4/6) / 1 = 4/6
So when dividing rational numbers, you can multiply the denominator by its reciprocal. This would be an example of converting a division problem into a multiplication one
<span>2500 + .42 X ≥ 8800 </span>
<span /><span><span>X <span>≥</span></span> 15,000</span>
<span /><span>The red circle is closed because the inequality is greater than or equal to 15,000
</span>
1. sqrt5 + 6sqrt5 = (1+6)sqrt5 = 7sqrt5 (answer is D)
2. 4sqrt2 - 7sqrt2 = (4-7)sqrt5 = -3sqrt2 (answer is B)
3. 3sqrt7 - sqrt63 = 3sqrt7 - sqrt7 * sqrt9 = 3sqrt7 - 3sqrt7 = 0 (answer is D)
4. -6sqrt10 + 5sqrt90 = -6sqrt10 + 5*(sqrt10 * sqrt9) = -6sqrt10 + 5*(3sqrt10)
= -6sqrt10 + 15sqrt10 = 9sqrt10 (answer is A)
5. sqrt6*(sqrt 2 + sqrt 3) = sqrt12 + sqrt18 = 2sqrt3 + 3sqrt2 (answer is D)
Answer:
which is not good for human survival
mark me as brainliest ❤️