What is the value of the 2 in 258,364

Find the value of x. also give me an explanation so i can complete it to other questions as well, : )

By what fraction name for 1 must 2/3 be multiplied to form a fraction with a denominator of 15

Carly made a beaded necklace. 4/18 of the beads are blue and 1/3 of the beads are green. use benchmark fractions to estimate about what fraction of the beads in the necklace are blue or green. explain