1. Three fourths of a number is 15. What's nine tenths of it? 2. One third of a number is equal to two fifths of three fourths Please make a formula

Let this number be X. just x multiplied by three fourths equals fifteen
So x is 15 divided by three quarters
That is: x equals fifteen times Four Thirds equals twenty
So x equals twenty
Twenty times nine tenths is eighteen
Two fifths of three fourths equals three tenths
Three tenths divided by one third is nine tenths

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