Answer:
i think it A
Step-by-step explanation:
Last choice 1 9/50
118/100 =
(2 × 59)/(22 × 52) =
((2 × 59) ÷ 2) / ((22 × 52) ÷ 2) =
59/(2 × 52) =
59/50
Then
59 ÷ 50 = 1 and remainder = 9 =>
59 = 1 × 50 + 9 =>
59/50 =
(1 × 50 + 9) / 50 =
1 + 9/50 =
1 9/50

now, notice, we use the decimal format for the percent, namely 17% is 17/100 or 0.17 and so on
so.... we know, whatever "x" and "y" is, they must add up to 100 grams
thus x + y = 100
and whatever the concentrated amount is, it must add up to 17 grams for the composition
thus 0.1x + 0.2y = 17

solve for "x", to see how much is needed of the 10% alloy
what about "y"? well, y = 100 - x