Since they are similar both dimensions would have the same ratio. The ratio of 5 and 15 is 3. 15 is 3 times larger than 5, so the unknown dimension is 3 times larger than the known dimension.
3 x 10 = 30
The unknown dimension is 30
270 / 3 ( (4 - 3) 3 - (-9) ) - 53
270 / 3 (1 x 3 - (-9) ) - 53
270 / 3 (3 + 9) - 53
270 / 3 x 12 - 53
In PEMDAS, with multiplication and division, you must go left to right, not multiplication then division.
90 x 12 - 53
1080 - 53
1027 is your answer
So 80% of 15 games won equal 12 games won and 3 lost. This is because 15/10 = 1.5 and 1.5 x 8 =12.
For 30, you do the exact same thing but with 90% instead. 30/10 = 3. 3 x 9 = 27.
So they need to have won 27 games to get a 90% winning percentage out of 30 games.
But since the question asks how many MORE games they need to play, it'll be 27-12 = 15.
So they need to win 15 more games to get a 90% winning percentage
2 71
3 86
4 101
6 131
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